| Message ID | 1595481999-121310-8-git-send-email-hzhou@ovn.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Avoid ARP flow explosion. | expand |
Bleep bloop. Greetings Han Zhou, I am a robot and I have tried out your patch.
Thanks for your contribution.
I encountered some error that I wasn't expecting. See the details below.
checkpatch:
WARNING: Line is 92 characters long (recommended limit is 79)
#370 FILE: ovn-nb.xml:1862:
<column name="options" key="always_learn_from_arp_request" type='{"type": "boolean"}'>
Lines checked: 438, Warnings: 1, Errors: 0
Please check this out. If you feel there has been an error, please email aconole@redhat.com
Thanks,
0-day Robot
On Thu, Jul 23, 2020 at 10:57 AM Han Zhou <hzhou@ovn.org> wrote: > Support a new logical router option "always_learn_from_arp_request" that > controls > behavior when handling ARP requests or IPv4 ND-NS packets. > > "true" - Always learn the MAC/IP binding and add a new MAC_Binding entry > (default behavior) > > "false" - If there is a MAC_binding for that IP and the MAC is different, > or, > if TPA of ARP request belongs to any router port on this router, then > update/add that MAC/IP binding. Otherwise, don't update/add entries. > > Reported-by: Girish Moodalbail <gmoodalbail@nvidia.com> > Reported-at: > https://mail.openvswitch.org/pipermail/ovs-discuss/2020-May/049995.html > Signed-off-by: Han Zhou <hzhou@ovn.org> > Hi Han, I just gave a quick look. I'll review properly tomorrow. I just have a few small comments now. I think it's good to add a few tests in ovn-northd.at to make sure that ovn-northd programs the flows as expected. Thanks Numan --- > northd/ovn-northd.8.xml | 109 > ++++++++++++++++++++++++++++++++++++++++-------- > northd/ovn-northd.c | 96 +++++++++++++++++++++++++++++++++++------- > ovn-nb.xml | 27 ++++++++++++ > tests/ovn.at | 18 ++++++++ > 4 files changed, 217 insertions(+), 33 deletions(-) > > diff --git a/northd/ovn-northd.8.xml b/northd/ovn-northd.8.xml > index 9f2c70f..30936ab 100644 > --- a/northd/ovn-northd.8.xml > +++ b/northd/ovn-northd.8.xml > @@ -1537,58 +1537,126 @@ output; > <p> > For each router port <var>P</var> that owns IP address > <var>A</var>, > which belongs to subnet <var>S</var> with prefix length > <var>L</var>, > - a priority-100 flow is added which matches > - <code>inport == <var>P</var> && > - arp.spa == <var>S</var>/<var>L</var> && arp.op == > 1</code> > - (ARP request) with the > - following actions: > + if the option <code>always_learn_from_arp_request</code> is > + <code>true</code> for this router, a priority-100 flow is added > which > + matches <code>inport == <var>P</var> && arp.spa == > + <var>S</var>/<var>L</var> && arp.op == 1</code> (ARP > request) > + with the following actions: > + </p> > + > + <pre> > +reg9[2] = lookup_arp(inport, arp.spa, arp.sha); > +next; > + </pre> > + > + <p> > + If the option <code>always_learn_from_arp_request</code> is > + <code>false</code>, the following two flows are added. > + </p> > + > + <p> > + A priority-110 flow is added which matches <code>inport == > + <var>P</var> && arp.spa == <var>S</var>/<var>L</var> > + && arp.tpa == <var>A</var> && arp.op == 1</code> > + (ARP request) with the following actions: > </p> > > <pre> > reg9[2] = lookup_arp(inport, arp.spa, arp.sha); > +reg9[3] = 1; > +next; > + </pre> > + > + <p> > + A priority-100 flow is added which matches <code>inport == > + <var>P</var> && arp.spa == <var>S</var>/<var>L</var> > + && arp.op == 1</code> (ARP request) with the following > + actions: > + </p> > + > + <pre> > +reg9[2] = lookup_arp(inport, arp.spa, arp.sha); > +reg9[3] = lookup_arp_ip(inport, arp.spa); > next; > </pre> > > <p> > If the logical router port <var>P</var> is a distributed gateway > router port, additional match > - <code>is_chassis_resident(cr-<var>P</var>)</code> is added so > that > - the resident gateway chassis handles the neighbor lookup. > + <code>is_chassis_resident(cr-<var>P</var>)</code> is added for > all > + these flows. > </p> > </li> > > <li> > <p> > A priority-100 flow which matches on ARP reply packets and > applies > - the actions: > + the actions if the option > <code>always_learn_from_arp_request</code> > + is <code>true</code>: > </p> > > <pre> > reg9[2] = lookup_arp(inport, arp.spa, arp.sha); > next; > </pre> > + > + <p> > + If the option <code>always_learn_from_arp_request</code> > + is <code>false</code>, the above actions will be: > + </p> > + > + <pre> > +reg9[2] = lookup_arp(inport, arp.spa, arp.sha); > +reg9[3] = 1; > +next; > + </pre> > + > </li> > > <li> > <p> > A priority-100 flow which matches on IPv6 Neighbor Discovery > - advertisement packet and applies the actions: > + advertisement packet and applies the actions if the option > + <code>always_learn_from_arp_request</code> is <code>true</code>: > </p> > > <pre> > reg9[2] = lookup_nd(inport, nd.target, nd.tll); > next; > </pre> > + > + <p> > + If the option <code>always_learn_from_arp_request</code> > + is <code>false</code>, the above actions will be: > + </p> > + > + <pre> > +reg9[2] = lookup_nd(inport, nd.target, nd.tll); > +reg9[3] = 1; > +next; > + </pre> > </li> > > <li> > <p> > A priority-100 flow which matches on IPv6 Neighbor Discovery > - solicitation packet and applies the actions: > + solicitation packet and applies the actions if the option > + <code>always_learn_from_arp_request</code> is <code>true</code>: > + </p> > + > + <pre> > +reg9[2] = lookup_nd(inport, ip6.src, nd.sll); > +next; > + </pre> > + > + <p> > + If the option <code>always_learn_from_arp_request</code> > + is <code>false</code>, the above actions will be: > </p> > > <pre> > reg9[2] = lookup_nd(inport, ip6.src, nd.sll); > +reg9[3] = lookup_nd_ip(inport, ip6.src); > next; > </pre> > </li> > @@ -1604,21 +1672,28 @@ next; > > <p> > This table adds flows to learn the mac bindings from the ARP and > - IPv6 Neighbor Solicitation/Advertisement packets if ARP/ND lookup > - failed in the previous table. > + IPv6 Neighbor Solicitation/Advertisement packets if it is needed > + according to the lookup results from the previous stage. > </p> > > <p> > reg9[2] will be <code>1</code> if the > <code>lookup_arp/lookup_nd</code> > - in the previous table was successful, or if there was no need to do > the > - lookup. > + in the previous table was successful or skipped, meaning no need > + to learn mac binding from the packet. > + </p> > + > + <p> > + reg9[3] will be <code>1</code> if the > + <code>lookup_arp_ip/lookup_nd_ip</code> in the previous table was > + successful or skipped, meaning it is ok to learn mac binding from > + the packet (if reg9[2] is 0). > </p> > > <ul> > <li> > - A priority-100 flow with the match > - <code>reg9[2] == 1</code> and advances the packet > - to the next table as there is no need to learn the neighbor. > + A priority-100 flow with the match <code>reg9[2] == 1 || reg9[3] > == > + 0</code> and advances the packet to the next table as there is no > need > + to learn the neighbor. > </li> > > <li> > diff --git a/northd/ovn-northd.c b/northd/ovn-northd.c > index 425f522..b5e7c08 100644 > --- a/northd/ovn-northd.c > +++ b/northd/ovn-northd.c > @@ -221,6 +221,7 @@ enum ovn_stage { > /* Register to store the result of check_pkt_larger action. */ > #define REGBIT_PKT_LARGER "reg9[1]" > #define REGBIT_LOOKUP_NEIGHBOR_RESULT "reg9[2]" > +#define REGBIT_LOOKUP_NEIGHBOR_IP_RESULT "reg9[3]" > > /* Register to store the eth address associated to a router port for > packets > * received in S_ROUTER_IN_ADMISSION. > @@ -8242,36 +8243,62 @@ build_lrouter_flows(struct hmap *datapaths, struct > hmap *ports, > * For ARP packets, table LOOKUP_NEIGHBOR does a lookup for the > * (arp.spa, arp.sha) in the mac binding table using the > 'lookup_arp' > * action and stores the result in REGBIT_LOOKUP_NEIGHBOR_RESULT > bit. > + * If "always_learn_from_arp_request" is set to false, it will > also > + * lookup for the (arp.spa) in the mac binding table using the > + * "lookup_arp_ip" action for ARP request packets, and stores the > + * result in REGBIT_LOOKUP_NEIGHBOR_IP_RESULT bit; or set that bit > + * to "1" directly for ARP response packets. > * > * For IPv6 ND NA packets, table LOOKUP_NEIGHBOR does a lookup > * for the (nd.target, nd.tll) in the mac binding table using the > * 'lookup_nd' action and stores the result in > - * REGBIT_LOOKUP_NEIGHBOR_RESULT bit. > + * REGBIT_LOOKUP_NEIGHBOR_RESULT bit. If > + * "always_learn_from_arp_request" is set to false, > + * REGBIT_LOOKUP_NEIGHBOR_IP_RESULT bit is set. > * > * For IPv6 ND NS packets, table LOOKUP_NEIGHBOR does a lookup > * for the (ip6.src, nd.sll) in the mac binding table using the > * 'lookup_nd' action and stores the result in > - * REGBIT_LOOKUP_NEIGHBOR_RESULT bit. > + * REGBIT_LOOKUP_NEIGHBOR_RESULT bit. If > + * "always_learn_from_arp_request" is set to false, it will also > lookup > + * for the (ip6.src) in the mac binding table using the > "lookup_nd_ip" > + * action and stores the result in > REGBIT_LOOKUP_NEIGHBOR_IP_RESULT > + * bit. > * > * Table LEARN_NEIGHBOR learns the mac-binding using the action > - * - 'put_arp/put_nd' only if REGBIT_LOOKUP_NEIGHBOR_RESULT bit > - * is not set. > + * - 'put_arp/put_nd'. Learning mac-binding is skipped if > + * REGBIT_LOOKUP_NEIGHBOR_RESULT bit is set or > + * REGBIT_LOOKUP_NEIGHBOR_IP_RESULT is not set. > * > * */ > > /* Flows for LOOKUP_NEIGHBOR. */ > + bool learn_from_arp_request = smap_get_bool(&od->nbr->options, > + "always_learn_from_arp_request", true); > + ds_clear(&actions); > + ds_put_format(&actions, REGBIT_LOOKUP_NEIGHBOR_RESULT > + " = lookup_arp(inport, arp.spa, arp.sha); %snext;", > + learn_from_arp_request ? "" : > + REGBIT_LOOKUP_NEIGHBOR_IP_RESULT" = 1; "); > ovn_lflow_add(lflows, od, S_ROUTER_IN_LOOKUP_NEIGHBOR, 100, > - "arp.op == 2", > - REGBIT_LOOKUP_NEIGHBOR_RESULT" = " > - "lookup_arp(inport, arp.spa, arp.sha); next;"); > + "arp.op == 2", ds_cstr(&actions)); > > + ds_clear(&actions); > + ds_put_format(&actions, REGBIT_LOOKUP_NEIGHBOR_RESULT > + " = lookup_nd(inport, nd.target, nd.tll); %snext;", > + learn_from_arp_request ? "" : > + REGBIT_LOOKUP_NEIGHBOR_IP_RESULT" = 1; "); > ovn_lflow_add(lflows, od, S_ROUTER_IN_LOOKUP_NEIGHBOR, 100, > "nd_na", > - REGBIT_LOOKUP_NEIGHBOR_RESULT" = " > - "lookup_nd(inport, nd.target, nd.tll); next;"); > + ds_cstr(&actions)); > > + ds_clear(&actions); > + ds_put_format(&actions, REGBIT_LOOKUP_NEIGHBOR_RESULT > + " = lookup_nd(inport, ip6.src, nd.sll); %snext;", > + learn_from_arp_request ? "" : > + REGBIT_LOOKUP_NEIGHBOR_IP_RESULT > + " = lookup_nd_ip(inport, ip6.src); "); > ovn_lflow_add(lflows, od, S_ROUTER_IN_LOOKUP_NEIGHBOR, 100, > "nd_ns", > - REGBIT_LOOKUP_NEIGHBOR_RESULT" = " > - "lookup_nd(inport, ip6.src, nd.sll); next;"); > + ds_cstr(&actions)); > > /* For other packet types, we can skip neighbor learning. > * So set REGBIT_LOOKUP_NEIGHBOR_RESULT to 1. */ > @@ -8280,8 +8307,12 @@ build_lrouter_flows(struct hmap *datapaths, struct > hmap *ports, > > /* Flows for LEARN_NEIGHBOR. */ > /* Skip Neighbor learning if not required. */ > + ds_clear(&match); > + ds_put_format(&match, REGBIT_LOOKUP_NEIGHBOR_RESULT" == 1%s", > + learn_from_arp_request ? "" : > + " || "REGBIT_LOOKUP_NEIGHBOR_IP_RESULT" == 0"); > ovn_lflow_add(lflows, od, S_ROUTER_IN_LEARN_NEIGHBOR, 100, > - REGBIT_LOOKUP_NEIGHBOR_RESULT" == 1", "next;"); > + ds_cstr(&match), "next;"); > > ovn_lflow_add(lflows, od, S_ROUTER_IN_LEARN_NEIGHBOR, 90, > "arp", "put_arp(inport, arp.spa, arp.sha); next;"); > @@ -8298,8 +8329,37 @@ build_lrouter_flows(struct hmap *datapaths, struct > hmap *ports, > continue; > } > > + bool learn_from_arp_request = smap_get_bool(&op->od->nbr->options, > + "always_learn_from_arp_request", true); > + > /* Check if we need to learn mac-binding from ARP requests. */ > for (int i = 0; i < op->lrp_networks.n_ipv4_addrs; i++) { > + if (!learn_from_arp_request) { > + /* ARP request to this address should always get learned, > + * so add a priority-110 flow to set > + * REGBIT_LOOKUP_NEIGHBOR_IP_RESULT to 1. */ > + ds_clear(&match); > + ds_put_format(&match, > + "inport == %s && arp.spa == %s/%u && " > + "arp.tpa == %s && arp.op == 1", > + op->json_key, > + op->lrp_networks.ipv4_addrs[i].network_s, > + op->lrp_networks.ipv4_addrs[i].plen, > + op->lrp_networks.ipv4_addrs[i].addr_s); > + if (op->od->l3dgw_port && op == op->od->l3dgw_port > + && op->od->l3redirect_port) { > + ds_put_format(&match, " && is_chassis_resident(%s)", > + op->od->l3redirect_port->json_key); > + } > + const char *actions_s = REGBIT_LOOKUP_NEIGHBOR_RESULT > + " = lookup_arp(inport, arp.spa, > arp.sha); " > + REGBIT_LOOKUP_NEIGHBOR_IP_RESULT" = 1;" > + " next;"; > + ovn_lflow_add_with_hint(lflows, op->od, > + S_ROUTER_IN_LOOKUP_NEIGHBOR, 110, > + ds_cstr(&match), actions_s, > + &op->nbrp->header_); > + } > ds_clear(&match); > ds_put_format(&match, > "inport == %s && arp.spa == %s/%u && arp.op == > 1", > @@ -8311,12 +8371,16 @@ build_lrouter_flows(struct hmap *datapaths, struct > hmap *ports, > ds_put_format(&match, " && is_chassis_resident(%s)", > op->od->l3redirect_port->json_key); > } > + ds_clear(&actions); > + ds_put_format(&actions, REGBIT_LOOKUP_NEIGHBOR_RESULT > + " = lookup_arp(inport, arp.spa, arp.sha); > %snext;", > + learn_from_arp_request ? "" : > + REGBIT_LOOKUP_NEIGHBOR_IP_RESULT > + " = lookup_arp_ip(inport, arp.spa); "); > ovn_lflow_add_with_hint(lflows, op->od, > S_ROUTER_IN_LOOKUP_NEIGHBOR, 100, > - ds_cstr(&match), > - REGBIT_LOOKUP_NEIGHBOR_RESULT" = " > - "lookup_arp(inport, arp.spa, > arp.sha); " > - "next;", &op->nbrp->header_); > + ds_cstr(&match), ds_cstr(&actions), > + &op->nbrp->header_); > } > } > > diff --git a/ovn-nb.xml b/ovn-nb.xml > index e8450aa..415d30a 100644 > --- a/ovn-nb.xml > +++ b/ovn-nb.xml > @@ -1859,6 +1859,33 @@ > send traffic between each other. > </p> > </column> > + <column name="options" key="always_learn_from_arp_request" > type='{"type": "boolean"}'> > + <p> > + This option controls the behavior when handling IPv4 ARP > requests or > + IPv6 ND-NS packets - whether a dynamic neighbor (MAC binding) > entry > + is added/updated. > + </p> > + > + <p> > + <code>true</code> - Always learn the MAC-IP binding, and > add/update > + the MAC binding entry. > + </p> > + > + <p> > + <code>false</code> - If there is a MAC binding for that IP and > the > + MAC is different, or, if TPA of ARP request belongs to any > router > + port on this router, then update/add that MAC-IP binding. > Otherwise, > + don't update/add entries. > + </p> > + > + <p> > + It is <code>true</code> by default. It is recommended to set to > + <code>false</code> when a large number of logical routers are > + connected to the same logical switch but most of them never > need to > + send traffic between each other, to reduce the size of the MAC > + binding table. > + </p> > + </column> > </group> > > <group title="Common Columns"> > diff --git a/tests/ovn.at b/tests/ovn.at > index 67fb754..fc811b4 100644 > --- a/tests/ovn.at > +++ b/tests/ovn.at > @@ -4031,6 +4031,18 @@ ip_to_hex() { > sha=f00000000011 > spa=`ip_to_hex 192 168 1 100` > tpa=$spa > + > +# When always_learn_from_arp_request=false, the new mac-binding will not > be learned > +# through GARP request. > +ovn-nbctl --wait=hv set logical_router lr0 > options:always_learn_from_arp_request=false > + > +test_arp 11 $sha $spa $tpa > +sleep 1 > Instead of sleep, I think it's good to run "ovn-nbctl --wait-hv sync" > +AT_CHECK([ovn-sbctl find mac_binding ip="192.168.1.100"], [0], []) > + > +# When always_learn_from_arp_request=true, the new mac-binding will be > learned. > +ovn-nbctl --wait=hv set logical_router lr0 > options:always_learn_from_arp_request=true > + > test_arp 11 $sha $spa $tpa > OVS_WAIT_UNTIL([test `ovn-sbctl find mac_binding ip="192.168.1.100" | wc > -l` -gt 0]) > ovn-nbctl --wait=hv sync > @@ -4045,6 +4057,12 @@ test_ip 21 $smac $dmac $sip $dip 11 > > # lp12 send GARP request to announce ownership of 192.168.1.100. > > +# Even when always_learn_from_arp_request=false, the existing mac-binding > should be > +# updated through GARP request. > +ovn-nbctl --wait=hv set logical_router lr0 > options:always_learn_from_arp_request=false > +ovn-sbctl lflow-list > +as hv2 ovs-ofctl dump-flows br-int > + > sha=f00000000012 > test_arp 12 $sha $spa $tpa > OVS_WAIT_UNTIL([ovn-sbctl find mac_binding ip="192.168.1.100" | grep > f0:00:00:00:00:12]) > -- > 2.1.0 > > _______________________________________________ > dev mailing list > dev@openvswitch.org > https://mail.openvswitch.org/mailman/listinfo/ovs-dev > >
On Wed, Jul 29, 2020 at 10:42 AM Numan Siddique <numans@ovn.org> wrote: > > > On Thu, Jul 23, 2020 at 10:57 AM Han Zhou <hzhou@ovn.org> wrote: > >> Support a new logical router option "always_learn_from_arp_request" that >> controls >> behavior when handling ARP requests or IPv4 ND-NS packets. >> >> "true" - Always learn the MAC/IP binding and add a new MAC_Binding entry >> (default behavior) >> >> "false" - If there is a MAC_binding for that IP and the MAC is different, >> or, >> if TPA of ARP request belongs to any router port on this router, then >> update/add that MAC/IP binding. Otherwise, don't update/add entries. >> >> Reported-by: Girish Moodalbail <gmoodalbail@nvidia.com> >> Reported-at: >> https://mail.openvswitch.org/pipermail/ovs-discuss/2020-May/049995.html >> Signed-off-by: Han Zhou <hzhou@ovn.org> >> > > Hi Han, > > I just gave a quick look. I'll review properly tomorrow. > > I just have a few small comments now. I think it's good to add a few tests > in ovn-northd.at > to make sure that ovn-northd programs the flows as expected. > > Hi Numan This patch already updated the existing test case in ovn.at to cover the scenario when always_learn_from_arp_request is set to false (and also flip back and forth to verify the mac binding is updated for existed entries). It verifies the behavior e2e, so I think maybe it is not necessary to add a separate test case just to check the lflows. What do you think? I sent v2 which added a test case for the first patch (it was not covered in the v1). Please take a look: https://patchwork.ozlabs.org/project/openvswitch/list/?series=194194 Thanks, Han > Thanks > Numan > > --- >> northd/ovn-northd.8.xml | 109 >> ++++++++++++++++++++++++++++++++++++++++-------- >> northd/ovn-northd.c | 96 +++++++++++++++++++++++++++++++++++------- >> ovn-nb.xml | 27 ++++++++++++ >> tests/ovn.at | 18 ++++++++ >> 4 files changed, 217 insertions(+), 33 deletions(-) >> >> diff --git a/northd/ovn-northd.8.xml b/northd/ovn-northd.8.xml >> index 9f2c70f..30936ab 100644 >> --- a/northd/ovn-northd.8.xml >> +++ b/northd/ovn-northd.8.xml >> @@ -1537,58 +1537,126 @@ output; >> <p> >> For each router port <var>P</var> that owns IP address >> <var>A</var>, >> which belongs to subnet <var>S</var> with prefix length >> <var>L</var>, >> - a priority-100 flow is added which matches >> - <code>inport == <var>P</var> && >> - arp.spa == <var>S</var>/<var>L</var> && arp.op == >> 1</code> >> - (ARP request) with the >> - following actions: >> + if the option <code>always_learn_from_arp_request</code> is >> + <code>true</code> for this router, a priority-100 flow is >> added which >> + matches <code>inport == <var>P</var> && arp.spa == >> + <var>S</var>/<var>L</var> && arp.op == 1</code> (ARP >> request) >> + with the following actions: >> + </p> >> + >> + <pre> >> +reg9[2] = lookup_arp(inport, arp.spa, arp.sha); >> +next; >> + </pre> >> + >> + <p> >> + If the option <code>always_learn_from_arp_request</code> is >> + <code>false</code>, the following two flows are added. >> + </p> >> + >> + <p> >> + A priority-110 flow is added which matches <code>inport == >> + <var>P</var> && arp.spa == <var>S</var>/<var>L</var> >> + && arp.tpa == <var>A</var> && arp.op == >> 1</code> >> + (ARP request) with the following actions: >> </p> >> >> <pre> >> reg9[2] = lookup_arp(inport, arp.spa, arp.sha); >> +reg9[3] = 1; >> +next; >> + </pre> >> + >> + <p> >> + A priority-100 flow is added which matches <code>inport == >> + <var>P</var> && arp.spa == <var>S</var>/<var>L</var> >> + && arp.op == 1</code> (ARP request) with the following >> + actions: >> + </p> >> + >> + <pre> >> +reg9[2] = lookup_arp(inport, arp.spa, arp.sha); >> +reg9[3] = lookup_arp_ip(inport, arp.spa); >> next; >> </pre> >> >> <p> >> If the logical router port <var>P</var> is a distributed >> gateway >> router port, additional match >> - <code>is_chassis_resident(cr-<var>P</var>)</code> is added so >> that >> - the resident gateway chassis handles the neighbor lookup. >> + <code>is_chassis_resident(cr-<var>P</var>)</code> is added for >> all >> + these flows. >> </p> >> </li> >> >> <li> >> <p> >> A priority-100 flow which matches on ARP reply packets and >> applies >> - the actions: >> + the actions if the option >> <code>always_learn_from_arp_request</code> >> + is <code>true</code>: >> </p> >> >> <pre> >> reg9[2] = lookup_arp(inport, arp.spa, arp.sha); >> next; >> </pre> >> + >> + <p> >> + If the option <code>always_learn_from_arp_request</code> >> + is <code>false</code>, the above actions will be: >> + </p> >> + >> + <pre> >> +reg9[2] = lookup_arp(inport, arp.spa, arp.sha); >> +reg9[3] = 1; >> +next; >> + </pre> >> + >> </li> >> >> <li> >> <p> >> A priority-100 flow which matches on IPv6 Neighbor Discovery >> - advertisement packet and applies the actions: >> + advertisement packet and applies the actions if the option >> + <code>always_learn_from_arp_request</code> is >> <code>true</code>: >> </p> >> >> <pre> >> reg9[2] = lookup_nd(inport, nd.target, nd.tll); >> next; >> </pre> >> + >> + <p> >> + If the option <code>always_learn_from_arp_request</code> >> + is <code>false</code>, the above actions will be: >> + </p> >> + >> + <pre> >> +reg9[2] = lookup_nd(inport, nd.target, nd.tll); >> +reg9[3] = 1; >> +next; >> + </pre> >> </li> >> >> <li> >> <p> >> A priority-100 flow which matches on IPv6 Neighbor Discovery >> - solicitation packet and applies the actions: >> + solicitation packet and applies the actions if the option >> + <code>always_learn_from_arp_request</code> is >> <code>true</code>: >> + </p> >> + >> + <pre> >> +reg9[2] = lookup_nd(inport, ip6.src, nd.sll); >> +next; >> + </pre> >> + >> + <p> >> + If the option <code>always_learn_from_arp_request</code> >> + is <code>false</code>, the above actions will be: >> </p> >> >> <pre> >> reg9[2] = lookup_nd(inport, ip6.src, nd.sll); >> +reg9[3] = lookup_nd_ip(inport, ip6.src); >> next; >> </pre> >> </li> >> @@ -1604,21 +1672,28 @@ next; >> >> <p> >> This table adds flows to learn the mac bindings from the ARP and >> - IPv6 Neighbor Solicitation/Advertisement packets if ARP/ND lookup >> - failed in the previous table. >> + IPv6 Neighbor Solicitation/Advertisement packets if it is needed >> + according to the lookup results from the previous stage. >> </p> >> >> <p> >> reg9[2] will be <code>1</code> if the >> <code>lookup_arp/lookup_nd</code> >> - in the previous table was successful, or if there was no need to >> do the >> - lookup. >> + in the previous table was successful or skipped, meaning no need >> + to learn mac binding from the packet. >> + </p> >> + >> + <p> >> + reg9[3] will be <code>1</code> if the >> + <code>lookup_arp_ip/lookup_nd_ip</code> in the previous table was >> + successful or skipped, meaning it is ok to learn mac binding from >> + the packet (if reg9[2] is 0). >> </p> >> >> <ul> >> <li> >> - A priority-100 flow with the match >> - <code>reg9[2] == 1</code> and advances the packet >> - to the next table as there is no need to learn the neighbor. >> + A priority-100 flow with the match <code>reg9[2] == 1 || reg9[3] >> == >> + 0</code> and advances the packet to the next table as there is >> no need >> + to learn the neighbor. >> </li> >> >> <li> >> diff --git a/northd/ovn-northd.c b/northd/ovn-northd.c >> index 425f522..b5e7c08 100644 >> --- a/northd/ovn-northd.c >> +++ b/northd/ovn-northd.c >> @@ -221,6 +221,7 @@ enum ovn_stage { >> /* Register to store the result of check_pkt_larger action. */ >> #define REGBIT_PKT_LARGER "reg9[1]" >> #define REGBIT_LOOKUP_NEIGHBOR_RESULT "reg9[2]" >> +#define REGBIT_LOOKUP_NEIGHBOR_IP_RESULT "reg9[3]" >> >> /* Register to store the eth address associated to a router port for >> packets >> * received in S_ROUTER_IN_ADMISSION. >> @@ -8242,36 +8243,62 @@ build_lrouter_flows(struct hmap *datapaths, >> struct hmap *ports, >> * For ARP packets, table LOOKUP_NEIGHBOR does a lookup for the >> * (arp.spa, arp.sha) in the mac binding table using the >> 'lookup_arp' >> * action and stores the result in REGBIT_LOOKUP_NEIGHBOR_RESULT >> bit. >> + * If "always_learn_from_arp_request" is set to false, it will >> also >> + * lookup for the (arp.spa) in the mac binding table using the >> + * "lookup_arp_ip" action for ARP request packets, and stores the >> + * result in REGBIT_LOOKUP_NEIGHBOR_IP_RESULT bit; or set that >> bit >> + * to "1" directly for ARP response packets. >> * >> * For IPv6 ND NA packets, table LOOKUP_NEIGHBOR does a lookup >> * for the (nd.target, nd.tll) in the mac binding table using the >> * 'lookup_nd' action and stores the result in >> - * REGBIT_LOOKUP_NEIGHBOR_RESULT bit. >> + * REGBIT_LOOKUP_NEIGHBOR_RESULT bit. If >> + * "always_learn_from_arp_request" is set to false, >> + * REGBIT_LOOKUP_NEIGHBOR_IP_RESULT bit is set. >> * >> * For IPv6 ND NS packets, table LOOKUP_NEIGHBOR does a lookup >> * for the (ip6.src, nd.sll) in the mac binding table using the >> * 'lookup_nd' action and stores the result in >> - * REGBIT_LOOKUP_NEIGHBOR_RESULT bit. >> + * REGBIT_LOOKUP_NEIGHBOR_RESULT bit. If >> + * "always_learn_from_arp_request" is set to false, it will also >> lookup >> + * for the (ip6.src) in the mac binding table using the >> "lookup_nd_ip" >> + * action and stores the result in >> REGBIT_LOOKUP_NEIGHBOR_IP_RESULT >> + * bit. >> * >> * Table LEARN_NEIGHBOR learns the mac-binding using the action >> - * - 'put_arp/put_nd' only if REGBIT_LOOKUP_NEIGHBOR_RESULT bit >> - * is not set. >> + * - 'put_arp/put_nd'. Learning mac-binding is skipped if >> + * REGBIT_LOOKUP_NEIGHBOR_RESULT bit is set or >> + * REGBIT_LOOKUP_NEIGHBOR_IP_RESULT is not set. >> * >> * */ >> >> /* Flows for LOOKUP_NEIGHBOR. */ >> + bool learn_from_arp_request = smap_get_bool(&od->nbr->options, >> + "always_learn_from_arp_request", true); >> + ds_clear(&actions); >> + ds_put_format(&actions, REGBIT_LOOKUP_NEIGHBOR_RESULT >> + " = lookup_arp(inport, arp.spa, arp.sha); %snext;", >> + learn_from_arp_request ? "" : >> + REGBIT_LOOKUP_NEIGHBOR_IP_RESULT" = 1; "); >> ovn_lflow_add(lflows, od, S_ROUTER_IN_LOOKUP_NEIGHBOR, 100, >> - "arp.op == 2", >> - REGBIT_LOOKUP_NEIGHBOR_RESULT" = " >> - "lookup_arp(inport, arp.spa, arp.sha); next;"); >> + "arp.op == 2", ds_cstr(&actions)); >> >> + ds_clear(&actions); >> + ds_put_format(&actions, REGBIT_LOOKUP_NEIGHBOR_RESULT >> + " = lookup_nd(inport, nd.target, nd.tll); %snext;", >> + learn_from_arp_request ? "" : >> + REGBIT_LOOKUP_NEIGHBOR_IP_RESULT" = 1; "); >> ovn_lflow_add(lflows, od, S_ROUTER_IN_LOOKUP_NEIGHBOR, 100, >> "nd_na", >> - REGBIT_LOOKUP_NEIGHBOR_RESULT" = " >> - "lookup_nd(inport, nd.target, nd.tll); next;"); >> + ds_cstr(&actions)); >> >> + ds_clear(&actions); >> + ds_put_format(&actions, REGBIT_LOOKUP_NEIGHBOR_RESULT >> + " = lookup_nd(inport, ip6.src, nd.sll); %snext;", >> + learn_from_arp_request ? "" : >> + REGBIT_LOOKUP_NEIGHBOR_IP_RESULT >> + " = lookup_nd_ip(inport, ip6.src); "); >> ovn_lflow_add(lflows, od, S_ROUTER_IN_LOOKUP_NEIGHBOR, 100, >> "nd_ns", >> - REGBIT_LOOKUP_NEIGHBOR_RESULT" = " >> - "lookup_nd(inport, ip6.src, nd.sll); next;"); >> + ds_cstr(&actions)); >> >> /* For other packet types, we can skip neighbor learning. >> * So set REGBIT_LOOKUP_NEIGHBOR_RESULT to 1. */ >> @@ -8280,8 +8307,12 @@ build_lrouter_flows(struct hmap *datapaths, struct >> hmap *ports, >> >> /* Flows for LEARN_NEIGHBOR. */ >> /* Skip Neighbor learning if not required. */ >> + ds_clear(&match); >> + ds_put_format(&match, REGBIT_LOOKUP_NEIGHBOR_RESULT" == 1%s", >> + learn_from_arp_request ? "" : >> + " || "REGBIT_LOOKUP_NEIGHBOR_IP_RESULT" == 0"); >> ovn_lflow_add(lflows, od, S_ROUTER_IN_LEARN_NEIGHBOR, 100, >> - REGBIT_LOOKUP_NEIGHBOR_RESULT" == 1", "next;"); >> + ds_cstr(&match), "next;"); >> >> ovn_lflow_add(lflows, od, S_ROUTER_IN_LEARN_NEIGHBOR, 90, >> "arp", "put_arp(inport, arp.spa, arp.sha); next;"); >> @@ -8298,8 +8329,37 @@ build_lrouter_flows(struct hmap *datapaths, struct >> hmap *ports, >> continue; >> } >> >> + bool learn_from_arp_request = >> smap_get_bool(&op->od->nbr->options, >> + "always_learn_from_arp_request", true); >> + >> /* Check if we need to learn mac-binding from ARP requests. */ >> for (int i = 0; i < op->lrp_networks.n_ipv4_addrs; i++) { >> + if (!learn_from_arp_request) { >> + /* ARP request to this address should always get learned, >> + * so add a priority-110 flow to set >> + * REGBIT_LOOKUP_NEIGHBOR_IP_RESULT to 1. */ >> + ds_clear(&match); >> + ds_put_format(&match, >> + "inport == %s && arp.spa == %s/%u && " >> + "arp.tpa == %s && arp.op == 1", >> + op->json_key, >> + op->lrp_networks.ipv4_addrs[i].network_s, >> + op->lrp_networks.ipv4_addrs[i].plen, >> + op->lrp_networks.ipv4_addrs[i].addr_s); >> + if (op->od->l3dgw_port && op == op->od->l3dgw_port >> + && op->od->l3redirect_port) { >> + ds_put_format(&match, " && is_chassis_resident(%s)", >> + op->od->l3redirect_port->json_key); >> + } >> + const char *actions_s = REGBIT_LOOKUP_NEIGHBOR_RESULT >> + " = lookup_arp(inport, arp.spa, >> arp.sha); " >> + REGBIT_LOOKUP_NEIGHBOR_IP_RESULT" = 1;" >> + " next;"; >> + ovn_lflow_add_with_hint(lflows, op->od, >> + S_ROUTER_IN_LOOKUP_NEIGHBOR, 110, >> + ds_cstr(&match), actions_s, >> + &op->nbrp->header_); >> + } >> ds_clear(&match); >> ds_put_format(&match, >> "inport == %s && arp.spa == %s/%u && arp.op == >> 1", >> @@ -8311,12 +8371,16 @@ build_lrouter_flows(struct hmap *datapaths, >> struct hmap *ports, >> ds_put_format(&match, " && is_chassis_resident(%s)", >> op->od->l3redirect_port->json_key); >> } >> + ds_clear(&actions); >> + ds_put_format(&actions, REGBIT_LOOKUP_NEIGHBOR_RESULT >> + " = lookup_arp(inport, arp.spa, arp.sha); >> %snext;", >> + learn_from_arp_request ? "" : >> + REGBIT_LOOKUP_NEIGHBOR_IP_RESULT >> + " = lookup_arp_ip(inport, arp.spa); "); >> ovn_lflow_add_with_hint(lflows, op->od, >> S_ROUTER_IN_LOOKUP_NEIGHBOR, 100, >> - ds_cstr(&match), >> - REGBIT_LOOKUP_NEIGHBOR_RESULT" = " >> - "lookup_arp(inport, arp.spa, >> arp.sha); " >> - "next;", &op->nbrp->header_); >> + ds_cstr(&match), ds_cstr(&actions), >> + &op->nbrp->header_); >> } >> } >> >> diff --git a/ovn-nb.xml b/ovn-nb.xml >> index e8450aa..415d30a 100644 >> --- a/ovn-nb.xml >> +++ b/ovn-nb.xml >> @@ -1859,6 +1859,33 @@ >> send traffic between each other. >> </p> >> </column> >> + <column name="options" key="always_learn_from_arp_request" >> type='{"type": "boolean"}'> >> + <p> >> + This option controls the behavior when handling IPv4 ARP >> requests or >> + IPv6 ND-NS packets - whether a dynamic neighbor (MAC binding) >> entry >> + is added/updated. >> + </p> >> + >> + <p> >> + <code>true</code> - Always learn the MAC-IP binding, and >> add/update >> + the MAC binding entry. >> + </p> >> + >> + <p> >> + <code>false</code> - If there is a MAC binding for that IP and >> the >> + MAC is different, or, if TPA of ARP request belongs to any >> router >> + port on this router, then update/add that MAC-IP binding. >> Otherwise, >> + don't update/add entries. >> + </p> >> + >> + <p> >> + It is <code>true</code> by default. It is recommended to set >> to >> + <code>false</code> when a large number of logical routers are >> + connected to the same logical switch but most of them never >> need to >> + send traffic between each other, to reduce the size of the MAC >> + binding table. >> + </p> >> + </column> >> </group> >> >> <group title="Common Columns"> >> diff --git a/tests/ovn.at b/tests/ovn.at >> index 67fb754..fc811b4 100644 >> --- a/tests/ovn.at >> +++ b/tests/ovn.at >> @@ -4031,6 +4031,18 @@ ip_to_hex() { >> sha=f00000000011 >> spa=`ip_to_hex 192 168 1 100` >> tpa=$spa >> + >> +# When always_learn_from_arp_request=false, the new mac-binding will not >> be learned >> +# through GARP request. >> +ovn-nbctl --wait=hv set logical_router lr0 >> options:always_learn_from_arp_request=false >> + >> +test_arp 11 $sha $spa $tpa >> +sleep 1 >> > > Instead of sleep, I think it's good to run "ovn-nbctl --wait-hv sync" > I thought about this, but since mac_binding learning is triggered by the data plane ARP packets instead of only DB changes, "ovn-nbctl --wait=hv sync" may still not help in race conditions. So I think sleep is the only way for now. > > >> +AT_CHECK([ovn-sbctl find mac_binding ip="192.168.1.100"], [0], []) >> + >> +# When always_learn_from_arp_request=true, the new mac-binding will be >> learned. >> +ovn-nbctl --wait=hv set logical_router lr0 >> options:always_learn_from_arp_request=true >> + >> test_arp 11 $sha $spa $tpa >> OVS_WAIT_UNTIL([test `ovn-sbctl find mac_binding ip="192.168.1.100" | wc >> -l` -gt 0]) >> ovn-nbctl --wait=hv sync >> @@ -4045,6 +4057,12 @@ test_ip 21 $smac $dmac $sip $dip 11 >> >> # lp12 send GARP request to announce ownership of 192.168.1.100. >> >> +# Even when always_learn_from_arp_request=false, the existing >> mac-binding should be >> +# updated through GARP request. >> +ovn-nbctl --wait=hv set logical_router lr0 >> options:always_learn_from_arp_request=false >> +ovn-sbctl lflow-list >> +as hv2 ovs-ofctl dump-flows br-int >> + >> sha=f00000000012 >> test_arp 12 $sha $spa $tpa >> OVS_WAIT_UNTIL([ovn-sbctl find mac_binding ip="192.168.1.100" | grep >> f0:00:00:00:00:12]) >> -- >> 2.1.0 >> >> _______________________________________________ >> dev mailing list >> dev@openvswitch.org >> https://mail.openvswitch.org/mailman/listinfo/ovs-dev >> >>
diff --git a/northd/ovn-northd.8.xml b/northd/ovn-northd.8.xml index 9f2c70f..30936ab 100644 --- a/northd/ovn-northd.8.xml +++ b/northd/ovn-northd.8.xml @@ -1537,58 +1537,126 @@ output; <p> For each router port <var>P</var> that owns IP address <var>A</var>, which belongs to subnet <var>S</var> with prefix length <var>L</var>, - a priority-100 flow is added which matches - <code>inport == <var>P</var> && - arp.spa == <var>S</var>/<var>L</var> && arp.op == 1</code> - (ARP request) with the - following actions: + if the option <code>always_learn_from_arp_request</code> is + <code>true</code> for this router, a priority-100 flow is added which + matches <code>inport == <var>P</var> && arp.spa == + <var>S</var>/<var>L</var> && arp.op == 1</code> (ARP request) + with the following actions: + </p> + + <pre> +reg9[2] = lookup_arp(inport, arp.spa, arp.sha); +next; + </pre> + + <p> + If the option <code>always_learn_from_arp_request</code> is + <code>false</code>, the following two flows are added. + </p> + + <p> + A priority-110 flow is added which matches <code>inport == + <var>P</var> && arp.spa == <var>S</var>/<var>L</var> + && arp.tpa == <var>A</var> && arp.op == 1</code> + (ARP request) with the following actions: </p> <pre> reg9[2] = lookup_arp(inport, arp.spa, arp.sha); +reg9[3] = 1; +next; + </pre> + + <p> + A priority-100 flow is added which matches <code>inport == + <var>P</var> && arp.spa == <var>S</var>/<var>L</var> + && arp.op == 1</code> (ARP request) with the following + actions: + </p> + + <pre> +reg9[2] = lookup_arp(inport, arp.spa, arp.sha); +reg9[3] = lookup_arp_ip(inport, arp.spa); next; </pre> <p> If the logical router port <var>P</var> is a distributed gateway router port, additional match - <code>is_chassis_resident(cr-<var>P</var>)</code> is added so that - the resident gateway chassis handles the neighbor lookup. + <code>is_chassis_resident(cr-<var>P</var>)</code> is added for all + these flows. </p> </li> <li> <p> A priority-100 flow which matches on ARP reply packets and applies - the actions: + the actions if the option <code>always_learn_from_arp_request</code> + is <code>true</code>: </p> <pre> reg9[2] = lookup_arp(inport, arp.spa, arp.sha); next; </pre> + + <p> + If the option <code>always_learn_from_arp_request</code> + is <code>false</code>, the above actions will be: + </p> + + <pre> +reg9[2] = lookup_arp(inport, arp.spa, arp.sha); +reg9[3] = 1; +next; + </pre> + </li> <li> <p> A priority-100 flow which matches on IPv6 Neighbor Discovery - advertisement packet and applies the actions: + advertisement packet and applies the actions if the option + <code>always_learn_from_arp_request</code> is <code>true</code>: </p> <pre> reg9[2] = lookup_nd(inport, nd.target, nd.tll); next; </pre> + + <p> + If the option <code>always_learn_from_arp_request</code> + is <code>false</code>, the above actions will be: + </p> + + <pre> +reg9[2] = lookup_nd(inport, nd.target, nd.tll); +reg9[3] = 1; +next; + </pre> </li> <li> <p> A priority-100 flow which matches on IPv6 Neighbor Discovery - solicitation packet and applies the actions: + solicitation packet and applies the actions if the option + <code>always_learn_from_arp_request</code> is <code>true</code>: + </p> + + <pre> +reg9[2] = lookup_nd(inport, ip6.src, nd.sll); +next; + </pre> + + <p> + If the option <code>always_learn_from_arp_request</code> + is <code>false</code>, the above actions will be: </p> <pre> reg9[2] = lookup_nd(inport, ip6.src, nd.sll); +reg9[3] = lookup_nd_ip(inport, ip6.src); next; </pre> </li> @@ -1604,21 +1672,28 @@ next; <p> This table adds flows to learn the mac bindings from the ARP and - IPv6 Neighbor Solicitation/Advertisement packets if ARP/ND lookup - failed in the previous table. + IPv6 Neighbor Solicitation/Advertisement packets if it is needed + according to the lookup results from the previous stage. </p> <p> reg9[2] will be <code>1</code> if the <code>lookup_arp/lookup_nd</code> - in the previous table was successful, or if there was no need to do the - lookup. + in the previous table was successful or skipped, meaning no need + to learn mac binding from the packet. + </p> + + <p> + reg9[3] will be <code>1</code> if the + <code>lookup_arp_ip/lookup_nd_ip</code> in the previous table was + successful or skipped, meaning it is ok to learn mac binding from + the packet (if reg9[2] is 0). </p> <ul> <li> - A priority-100 flow with the match - <code>reg9[2] == 1</code> and advances the packet - to the next table as there is no need to learn the neighbor. + A priority-100 flow with the match <code>reg9[2] == 1 || reg9[3] == + 0</code> and advances the packet to the next table as there is no need + to learn the neighbor. </li> <li> diff --git a/northd/ovn-northd.c b/northd/ovn-northd.c index 425f522..b5e7c08 100644 --- a/northd/ovn-northd.c +++ b/northd/ovn-northd.c @@ -221,6 +221,7 @@ enum ovn_stage { /* Register to store the result of check_pkt_larger action. */ #define REGBIT_PKT_LARGER "reg9[1]" #define REGBIT_LOOKUP_NEIGHBOR_RESULT "reg9[2]" +#define REGBIT_LOOKUP_NEIGHBOR_IP_RESULT "reg9[3]" /* Register to store the eth address associated to a router port for packets * received in S_ROUTER_IN_ADMISSION. @@ -8242,36 +8243,62 @@ build_lrouter_flows(struct hmap *datapaths, struct hmap *ports, * For ARP packets, table LOOKUP_NEIGHBOR does a lookup for the * (arp.spa, arp.sha) in the mac binding table using the 'lookup_arp' * action and stores the result in REGBIT_LOOKUP_NEIGHBOR_RESULT bit. + * If "always_learn_from_arp_request" is set to false, it will also + * lookup for the (arp.spa) in the mac binding table using the + * "lookup_arp_ip" action for ARP request packets, and stores the + * result in REGBIT_LOOKUP_NEIGHBOR_IP_RESULT bit; or set that bit + * to "1" directly for ARP response packets. * * For IPv6 ND NA packets, table LOOKUP_NEIGHBOR does a lookup * for the (nd.target, nd.tll) in the mac binding table using the * 'lookup_nd' action and stores the result in - * REGBIT_LOOKUP_NEIGHBOR_RESULT bit. + * REGBIT_LOOKUP_NEIGHBOR_RESULT bit. If + * "always_learn_from_arp_request" is set to false, + * REGBIT_LOOKUP_NEIGHBOR_IP_RESULT bit is set. * * For IPv6 ND NS packets, table LOOKUP_NEIGHBOR does a lookup * for the (ip6.src, nd.sll) in the mac binding table using the * 'lookup_nd' action and stores the result in - * REGBIT_LOOKUP_NEIGHBOR_RESULT bit. + * REGBIT_LOOKUP_NEIGHBOR_RESULT bit. If + * "always_learn_from_arp_request" is set to false, it will also lookup + * for the (ip6.src) in the mac binding table using the "lookup_nd_ip" + * action and stores the result in REGBIT_LOOKUP_NEIGHBOR_IP_RESULT + * bit. * * Table LEARN_NEIGHBOR learns the mac-binding using the action - * - 'put_arp/put_nd' only if REGBIT_LOOKUP_NEIGHBOR_RESULT bit - * is not set. + * - 'put_arp/put_nd'. Learning mac-binding is skipped if + * REGBIT_LOOKUP_NEIGHBOR_RESULT bit is set or + * REGBIT_LOOKUP_NEIGHBOR_IP_RESULT is not set. * * */ /* Flows for LOOKUP_NEIGHBOR. */ + bool learn_from_arp_request = smap_get_bool(&od->nbr->options, + "always_learn_from_arp_request", true); + ds_clear(&actions); + ds_put_format(&actions, REGBIT_LOOKUP_NEIGHBOR_RESULT + " = lookup_arp(inport, arp.spa, arp.sha); %snext;", + learn_from_arp_request ? "" : + REGBIT_LOOKUP_NEIGHBOR_IP_RESULT" = 1; "); ovn_lflow_add(lflows, od, S_ROUTER_IN_LOOKUP_NEIGHBOR, 100, - "arp.op == 2", - REGBIT_LOOKUP_NEIGHBOR_RESULT" = " - "lookup_arp(inport, arp.spa, arp.sha); next;"); + "arp.op == 2", ds_cstr(&actions)); + ds_clear(&actions); + ds_put_format(&actions, REGBIT_LOOKUP_NEIGHBOR_RESULT + " = lookup_nd(inport, nd.target, nd.tll); %snext;", + learn_from_arp_request ? "" : + REGBIT_LOOKUP_NEIGHBOR_IP_RESULT" = 1; "); ovn_lflow_add(lflows, od, S_ROUTER_IN_LOOKUP_NEIGHBOR, 100, "nd_na", - REGBIT_LOOKUP_NEIGHBOR_RESULT" = " - "lookup_nd(inport, nd.target, nd.tll); next;"); + ds_cstr(&actions)); + ds_clear(&actions); + ds_put_format(&actions, REGBIT_LOOKUP_NEIGHBOR_RESULT + " = lookup_nd(inport, ip6.src, nd.sll); %snext;", + learn_from_arp_request ? "" : + REGBIT_LOOKUP_NEIGHBOR_IP_RESULT + " = lookup_nd_ip(inport, ip6.src); "); ovn_lflow_add(lflows, od, S_ROUTER_IN_LOOKUP_NEIGHBOR, 100, "nd_ns", - REGBIT_LOOKUP_NEIGHBOR_RESULT" = " - "lookup_nd(inport, ip6.src, nd.sll); next;"); + ds_cstr(&actions)); /* For other packet types, we can skip neighbor learning. * So set REGBIT_LOOKUP_NEIGHBOR_RESULT to 1. */ @@ -8280,8 +8307,12 @@ build_lrouter_flows(struct hmap *datapaths, struct hmap *ports, /* Flows for LEARN_NEIGHBOR. */ /* Skip Neighbor learning if not required. */ + ds_clear(&match); + ds_put_format(&match, REGBIT_LOOKUP_NEIGHBOR_RESULT" == 1%s", + learn_from_arp_request ? "" : + " || "REGBIT_LOOKUP_NEIGHBOR_IP_RESULT" == 0"); ovn_lflow_add(lflows, od, S_ROUTER_IN_LEARN_NEIGHBOR, 100, - REGBIT_LOOKUP_NEIGHBOR_RESULT" == 1", "next;"); + ds_cstr(&match), "next;"); ovn_lflow_add(lflows, od, S_ROUTER_IN_LEARN_NEIGHBOR, 90, "arp", "put_arp(inport, arp.spa, arp.sha); next;"); @@ -8298,8 +8329,37 @@ build_lrouter_flows(struct hmap *datapaths, struct hmap *ports, continue; } + bool learn_from_arp_request = smap_get_bool(&op->od->nbr->options, + "always_learn_from_arp_request", true); + /* Check if we need to learn mac-binding from ARP requests. */ for (int i = 0; i < op->lrp_networks.n_ipv4_addrs; i++) { + if (!learn_from_arp_request) { + /* ARP request to this address should always get learned, + * so add a priority-110 flow to set + * REGBIT_LOOKUP_NEIGHBOR_IP_RESULT to 1. */ + ds_clear(&match); + ds_put_format(&match, + "inport == %s && arp.spa == %s/%u && " + "arp.tpa == %s && arp.op == 1", + op->json_key, + op->lrp_networks.ipv4_addrs[i].network_s, + op->lrp_networks.ipv4_addrs[i].plen, + op->lrp_networks.ipv4_addrs[i].addr_s); + if (op->od->l3dgw_port && op == op->od->l3dgw_port + && op->od->l3redirect_port) { + ds_put_format(&match, " && is_chassis_resident(%s)", + op->od->l3redirect_port->json_key); + } + const char *actions_s = REGBIT_LOOKUP_NEIGHBOR_RESULT + " = lookup_arp(inport, arp.spa, arp.sha); " + REGBIT_LOOKUP_NEIGHBOR_IP_RESULT" = 1;" + " next;"; + ovn_lflow_add_with_hint(lflows, op->od, + S_ROUTER_IN_LOOKUP_NEIGHBOR, 110, + ds_cstr(&match), actions_s, + &op->nbrp->header_); + } ds_clear(&match); ds_put_format(&match, "inport == %s && arp.spa == %s/%u && arp.op == 1", @@ -8311,12 +8371,16 @@ build_lrouter_flows(struct hmap *datapaths, struct hmap *ports, ds_put_format(&match, " && is_chassis_resident(%s)", op->od->l3redirect_port->json_key); } + ds_clear(&actions); + ds_put_format(&actions, REGBIT_LOOKUP_NEIGHBOR_RESULT + " = lookup_arp(inport, arp.spa, arp.sha); %snext;", + learn_from_arp_request ? "" : + REGBIT_LOOKUP_NEIGHBOR_IP_RESULT + " = lookup_arp_ip(inport, arp.spa); "); ovn_lflow_add_with_hint(lflows, op->od, S_ROUTER_IN_LOOKUP_NEIGHBOR, 100, - ds_cstr(&match), - REGBIT_LOOKUP_NEIGHBOR_RESULT" = " - "lookup_arp(inport, arp.spa, arp.sha); " - "next;", &op->nbrp->header_); + ds_cstr(&match), ds_cstr(&actions), + &op->nbrp->header_); } } diff --git a/ovn-nb.xml b/ovn-nb.xml index e8450aa..415d30a 100644 --- a/ovn-nb.xml +++ b/ovn-nb.xml @@ -1859,6 +1859,33 @@ send traffic between each other. </p> </column> + <column name="options" key="always_learn_from_arp_request" type='{"type": "boolean"}'> + <p> + This option controls the behavior when handling IPv4 ARP requests or + IPv6 ND-NS packets - whether a dynamic neighbor (MAC binding) entry + is added/updated. + </p> + + <p> + <code>true</code> - Always learn the MAC-IP binding, and add/update + the MAC binding entry. + </p> + + <p> + <code>false</code> - If there is a MAC binding for that IP and the + MAC is different, or, if TPA of ARP request belongs to any router + port on this router, then update/add that MAC-IP binding. Otherwise, + don't update/add entries. + </p> + + <p> + It is <code>true</code> by default. It is recommended to set to + <code>false</code> when a large number of logical routers are + connected to the same logical switch but most of them never need to + send traffic between each other, to reduce the size of the MAC + binding table. + </p> + </column> </group> <group title="Common Columns"> diff --git a/tests/ovn.at b/tests/ovn.at index 67fb754..fc811b4 100644 --- a/tests/ovn.at +++ b/tests/ovn.at @@ -4031,6 +4031,18 @@ ip_to_hex() { sha=f00000000011 spa=`ip_to_hex 192 168 1 100` tpa=$spa + +# When always_learn_from_arp_request=false, the new mac-binding will not be learned +# through GARP request. +ovn-nbctl --wait=hv set logical_router lr0 options:always_learn_from_arp_request=false + +test_arp 11 $sha $spa $tpa +sleep 1 +AT_CHECK([ovn-sbctl find mac_binding ip="192.168.1.100"], [0], []) + +# When always_learn_from_arp_request=true, the new mac-binding will be learned. +ovn-nbctl --wait=hv set logical_router lr0 options:always_learn_from_arp_request=true + test_arp 11 $sha $spa $tpa OVS_WAIT_UNTIL([test `ovn-sbctl find mac_binding ip="192.168.1.100" | wc -l` -gt 0]) ovn-nbctl --wait=hv sync @@ -4045,6 +4057,12 @@ test_ip 21 $smac $dmac $sip $dip 11 # lp12 send GARP request to announce ownership of 192.168.1.100. +# Even when always_learn_from_arp_request=false, the existing mac-binding should be +# updated through GARP request. +ovn-nbctl --wait=hv set logical_router lr0 options:always_learn_from_arp_request=false +ovn-sbctl lflow-list +as hv2 ovs-ofctl dump-flows br-int + sha=f00000000012 test_arp 12 $sha $spa $tpa OVS_WAIT_UNTIL([ovn-sbctl find mac_binding ip="192.168.1.100" | grep f0:00:00:00:00:12])
Support a new logical router option "always_learn_from_arp_request" that controls behavior when handling ARP requests or IPv4 ND-NS packets. "true" - Always learn the MAC/IP binding and add a new MAC_Binding entry (default behavior) "false" - If there is a MAC_binding for that IP and the MAC is different, or, if TPA of ARP request belongs to any router port on this router, then update/add that MAC/IP binding. Otherwise, don't update/add entries. Reported-by: Girish Moodalbail <gmoodalbail@nvidia.com> Reported-at: https://mail.openvswitch.org/pipermail/ovs-discuss/2020-May/049995.html Signed-off-by: Han Zhou <hzhou@ovn.org> --- northd/ovn-northd.8.xml | 109 ++++++++++++++++++++++++++++++++++++++++-------- northd/ovn-northd.c | 96 +++++++++++++++++++++++++++++++++++------- ovn-nb.xml | 27 ++++++++++++ tests/ovn.at | 18 ++++++++ 4 files changed, 217 insertions(+), 33 deletions(-)