diff --git a/ovn/northd/ovn-northd.c b/ovn/northd/ovn-northd.c
index 0874a9c..5c7806f 100644
--- a/ovn/northd/ovn-northd.c
+++ b/ovn/northd/ovn-northd.c
@@ -123,9 +123,10 @@ enum ovn_stage {
     PIPELINE_STAGE(ROUTER, IN,  IP_INPUT,    1, "lr_in_ip_input")     \
     PIPELINE_STAGE(ROUTER, IN,  UNSNAT,      2, "lr_in_unsnat")       \
     PIPELINE_STAGE(ROUTER, IN,  DNAT,        3, "lr_in_dnat")         \
-    PIPELINE_STAGE(ROUTER, IN,  IP_ROUTING,  4, "lr_in_ip_routing")   \
-    PIPELINE_STAGE(ROUTER, IN,  ARP_RESOLVE, 5, "lr_in_arp_resolve")  \
-    PIPELINE_STAGE(ROUTER, IN,  ARP_REQUEST, 6, "lr_in_arp_request")  \
+    PIPELINE_STAGE(ROUTER, IN,  RS_RSP,      4, "lr_in_rs_rsp")      \
+    PIPELINE_STAGE(ROUTER, IN,  IP_ROUTING,  5, "lr_in_ip_routing")   \
+    PIPELINE_STAGE(ROUTER, IN,  ARP_RESOLVE, 6, "lr_in_arp_resolve")  \
+    PIPELINE_STAGE(ROUTER, IN,  ARP_REQUEST, 7, "lr_in_arp_request")  \
                                                                       \
     /* Logical router egress stages. */                               \
     PIPELINE_STAGE(ROUTER, OUT, SNAT,      0, "lr_out_snat")          \
@@ -2721,6 +2722,32 @@ build_lswitch_flows(struct hmap *datapaths, struct hmap *ports,
         ovn_lflow_add(lflows, od, S_SWITCH_IN_DHCP_RESPONSE, 0, "1", "next;");
     }
 
+    /* Ingress table 12: Destination lookup, router solicitation handling
+     * (priority 110). */
+    HMAP_FOR_EACH (od, key_node, datapaths) {
+        if (!od->nbs) {
+            continue;
+        }
+
+        if (!od->n_router_ports) {
+            continue;
+        }
+
+        ds_clear(&actions);
+        for (size_t i = 0; i != od->n_router_ports; i++) {
+            op = od->router_ports[i];
+            if (!op->lsp_addrs || !op->lsp_addrs->n_ipv6_addrs) {
+                continue;
+            }
+            ds_put_format(&actions, "outport = %s; output; ", op->json_key);
+        }
+        if (actions.length != 0) {
+            ds_chomp(&actions, ' ');
+            ovn_lflow_add(lflows, od, S_SWITCH_IN_L2_LKUP, 110, "nd_rs",
+                          ds_cstr(&actions));
+        }
+    }
+
     /* Ingress table 12: Destination lookup, broadcast and multicast handling
      * (priority 100). */
     HMAP_FOR_EACH (op, key_node, ports) {
@@ -3548,7 +3575,65 @@ build_lrouter_flows(struct hmap *datapaths, struct hmap *ports,
                       "ip", "flags.loopback = 1; ct_dnat;");
     }
 
-    /* Logical router ingress table 4: IP Routing.
+    /* Logical router ingress table 4: RS responder, by default goto next.
+     * (priority 0)*/
+    HMAP_FOR_EACH (od, key_node, datapaths) {
+        if (!od->nbr) {
+            continue;
+        }
+
+        ovn_lflow_add(lflows, od, S_ROUTER_IN_RS_RSP, 0, "1", "next;");
+    }
+
+    /* Logical router ingress table 4: RS responder, reply for 'slaac' enabled
+     * router port. (priority 50)*/
+    HMAP_FOR_EACH (op, key_node, ports) {
+        if (!op->nbrp || op->nbrp->peer
+            || !op->peer
+            || !op->nbrp->slaac
+            || !*op->nbrp->slaac) {
+            continue;
+        }
+
+        ds_clear(&match);
+        ds_put_format(&match, "inport == %s && ip6.dst == ff02::2 && nd_rs",
+                              op->json_key);
+        ds_clear(&actions);
+        const char *mtu_s = smap_get(&op->peer->od->nbs->other_config, "mtu");
+        uint32_t mtu = (!mtu_s || atoi(mtu_s) < 1280) ? 1280 : atoi(mtu_s);
+        ds_put_format(&actions, "nd_ra{put_nd_ra(64,0,10800,0,0); "
+                                "put_nd_opt_sll(%s); "
+                                "put_nd_opt_mtu(%u); ",
+                                op->lrp_networks.ea_s,
+                                mtu);
+        size_t actions_len = actions.length;
+        for (size_t i = 0; i != op->lrp_networks.n_ipv6_addrs; i++) {
+            if (in6_is_lla(&op->lrp_networks.ipv6_addrs[i].network)) {
+                continue;
+            }
+            ds_put_format(&actions,
+                          "put_nd_opt_prefix(%u,%u,10800,10800,%s); ",
+                          op->lrp_networks.ipv6_addrs[i].plen,
+                          (ND_PREFIX_ON_LINK | ND_PREFIX_AUTONOMOUS_ADDRESS),
+                          op->lrp_networks.ipv6_addrs[i].network_s);
+        }
+        if (actions.length != actions_len) {
+            char ip6_str[INET6_ADDRSTRLEN + 1];
+            struct in6_addr lla;
+            in6_generate_lla(op->lrp_networks.ea, &lla);
+            memset(ip6_str, 0, sizeof(ip6_str));
+            ipv6_string_mapped(ip6_str, &lla);
+            ds_put_format(&actions, "eth.src = %s; ip6.src = %s; "
+                                    "outport = inport; flags.loopback = 1; "
+                                    "output;};",
+                                    op->lrp_networks.ea_s,
+                                    ip6_str);
+            ovn_lflow_add(lflows, op->od, S_ROUTER_IN_RS_RSP, 50,
+                          ds_cstr(&match), ds_cstr(&actions));
+        }
+    }
+
+    /* Logical router ingress table 5: IP Routing.
      *
      * A packet that arrives at this table is an IP packet that should be
      * routed to the address in 'ip[46].dst'. This table sets outport to
@@ -3590,7 +3675,7 @@ build_lrouter_flows(struct hmap *datapaths, struct hmap *ports,
 
     /* XXX destination unreachable */
 
-    /* Local router ingress table 5: ARP Resolution.
+    /* Local router ingress table 6: ARP Resolution.
      *
      * Any packet that reaches this table is an IP packet whose next-hop IP
      * address is in reg0. (ip4.dst is the final destination.) This table
@@ -3787,7 +3872,7 @@ build_lrouter_flows(struct hmap *datapaths, struct hmap *ports,
                       "get_nd(outport, xxreg0); next;");
     }
 
-    /* Local router ingress table 6: ARP request.
+    /* Local router ingress table 7: ARP request.
      *
      * In the common case where the Ethernet destination has been resolved,
      * this table outputs the packet (priority 0).  Otherwise, it composes
diff --git a/ovn/ovn-nb.ovsschema b/ovn/ovn-nb.ovsschema
index 456ae98..3c0361a 100644
--- a/ovn/ovn-nb.ovsschema
+++ b/ovn/ovn-nb.ovsschema
@@ -1,7 +1,7 @@
 {
     "name": "OVN_Northbound",
-    "version": "5.3.1",
-    "cksum": "1921908091 9353",
+    "version": "5.3.2",
+    "cksum": "1681625340 9428",
     "tables": {
         "NB_Global": {
             "columns": {
@@ -154,6 +154,7 @@
                                       "max": "unlimited"}},
                 "mac": {"type": "string"},
                 "peer": {"type": {"key": "string", "min": 0, "max": 1}},
+                "slaac": {"type": {"key": "boolean", "min": 0, "max": 1}},
                 "enabled": {"type": {"key": "boolean", "min": 0, "max": 1}},
                 "external_ids": {
                     "type": {"key": "string", "value": "string",
diff --git a/ovn/ovn-nb.xml b/ovn/ovn-nb.xml
index 5719e74..5ed2709 100644
--- a/ovn/ovn-nb.xml
+++ b/ovn/ovn-nb.xml
@@ -132,6 +132,10 @@
         column="addresses"/> column to request dynamic address assignment for a
         particular port.
       </column>
+
+      <column name="other_config" key="mtu">
+        MTU of logical switch.
+      </column>
     </group>
 
     <group title="Common Columns">
@@ -913,6 +917,13 @@
       The Ethernet address that belongs to this router port.
     </column>
 
+    <column name="slaac">
+      Setting <code>true</code> specifies the logical switch subnets behind
+      this router port IPv6 networks are going to use SLAAC as IPv6 address
+      configuration and RA mode. Otherwise set this column to
+      <code>false</code>, or this router port has no IPv6 networks.
+    </column>
+
     <column name="enabled">
       This column is used to administratively set port state.  If this column
       is empty or is set to <code>true</code>, the port is enabled.  If this
diff --git a/tests/ovn.at b/tests/ovn.at
index 3091131..6b4f72c 100644
--- a/tests/ovn.at
+++ b/tests/ovn.at
@@ -4983,3 +4983,117 @@ cat packets
 OVN_CLEANUP([hv1])
 
 AT_CLEANUP
+
+AT_SETUP([ovn -- nd_ra ])
+AT_KEYWORDS([ovn-nd_ra])
+AT_SKIP_IF([test $HAVE_PYTHON = no])
+ovn_start
+
+# In this test case we create 1 lswitch with 2 VIF ports attached,
+# and a lrouter connected to the lswitch.
+# Router solicitation packet we test, sent from VIF port, will be replied
+# by local ovn-controller.
+
+# Create hypervisors and logical switch lsw0, logical router lr0, attach lsw0
+# onto lr0, set Logical_Router_Port.slaac column to 'true' to allow lrp0 send
+# RA for SLAAC mode.
+ovn-nbctl ls-add lsw0
+ovn-nbctl lr-add lr0
+ovn-nbctl lrp-add lr0 lrp0 fa:16:3e:00:00:01 fdad:1234:5678::1/64
+ovn-nbctl set Logical_Router_Port lrp0 slaac="true"
+ovn-nbctl \
+    -- lsp-add lsw0 lsp0 \
+    -- set Logical_Switch_Port lsp0 type=router \
+                     options:router-port=lrp0 \
+                     addresses='"fa:16:3e:00:00:01 fdad:1234:5678::1"'
+net_add n1
+sim_add hv1
+as hv1
+ovs-vsctl add-br br-phys
+ovn_attach n1 br-phys 192.168.0.2
+
+# Add vif1 to hv1 and lsw0, turn on l2 port security on vif1.
+ovs-vsctl add-port br-int vif1 -- set Interface vif1 external-ids:iface-id=lp1 options:tx_pcap=hv1/vif1-tx.pcap options:rxq_pcap=hv1/vif1-rx.pcap
+ovn-nbctl lsp-add lsw0 lp1
+ovn-nbctl lsp-set-addresses lp1 "fa:16:3e:00:00:02 10.0.0.12 fdad:1234:5678:0:f816:3eff:fe:2"
+ovn-nbctl lsp-set-port-security lp1 "fa:16:3e:00:00:02 10.0.0.12 fdad:1234:5678:0:f816:3eff:fe:2"
+
+# Add vif2 to hv1 and lsw0, turn on l2 port security on vif2.
+ovs-vsctl add-port br-int vif2 -- set Interface vif2 external-ids:iface-id=lp2 options:tx_pcap=hv1/vif2-tx.pcap options:rxq_pcap=hv1/vif2-rx.pcap
+ovn-nbctl lsp-add lsw0 lp2
+ovn-nbctl lsp-set-addresses lp2 "fa:16:3e:00:00:03 10.0.0.13 fdad:1234:5678:0:f816:3eff:fe:3"
+ovn-nbctl lsp-set-port-security lp2 "fa:16:3e:00:00:03 10.0.0.13 fdad:1234:5678:0:f816:3eff:fe:3"
+
+# Add ACL rule for ICMPv6 on lsw0
+ovn-nbctl acl-add lsw0 from-lport 1002 'ip6 && icmp6'  allow-related
+ovn-nbctl acl-add lsw0 to-lport 1002 'outport == "lp1" && ip6 && icmp6'  allow-related
+ovn-nbctl acl-add lsw0 to-lport 1002 'outport == "lp2" && ip6 && icmp6'  allow-related
+
+# Allow some time for ovn-northd and ovn-controller to catch up.
+# XXX This should be more systematic.
+sleep 1
+
+# Given the name of a logical port, prints the name of the hypervisor
+# on which it is located.
+vif_to_hv() {
+    echo hv1${1%?}
+}
+trim_zeros() {
+    sed 's/\(00\)\{1,\}$//'
+}
+for i in 1 2; do
+    : > $i.expected
+done
+
+# Complete Router Solicitation packet and Router Advertisement packet for vif1.
+rs_packet=333300000002fa163e00000286dd6000000000103afffe80000000000000f8163efffe000002ff02000000000000000000000000000285000efc000000000101fa163e000002
+packet_l2=fa163e000002fa163e00000186dd
+packet_l3=6000000000403afffe80000000000000f8163efffe000001fe80000000000000f8163efffe000002
+packet_l4_hd_no_csum=860040002a300000000000000000
+sll_opt=0101fa163e000001
+mtu_opt=0501000000000500
+prefix_opt=030440c000002a3000002a3000000000fdad1234567800000000000000000000
+ra_packet=$packet_l2$packet_l3$packet_l4_hd_no_csum$sll_opt$mtu_opt$prefix_opt
+
+as hv1 ovs-appctl netdev-dummy/receive vif1 $rs_packet
+echo $ra_packet | trim_zeros >> 1.expected
+
+sleep 1
+
+# Extend lrp0 networks, update lp2 addresses and l2 port security.
+ovn-nbctl add Logical_Router_Port lrp0 networks \"fdad:9abc:def::1/64\"
+ovn-nbctl set Logical_Switch_Port lp2 addresses \"fa:16:3e:00:00:03 10.0.0.13 fdad:1234:5678:0:f816:3eff:fe:3 fdad:9abc:def:0:f816:3eff:fe:3
+ovn-nbctl set Logical_Switch_Port lp2 port-security \"fa:16:3e:00:00:03 10.0.0.13 fdad:1234:5678:0:f816:3eff:fe:3 fdad:9abc:def:0:f816:3eff:fe:3
+# Update lsw0 other_config with mtu
+ovn-nbctl add logical-switch lsw0 other_config mtu=1450
+# Update Router solicitation packet for lp2.
+rs_packet=333300000002fa163e00000386dd6000000000103afffe80000000000000f8163efffe000003ff02000000000000000000000000000285000efa000000000101fa163e000003
+# Router Advertisement packet should have a new mtu option and a prefix information option.
+packet_l2=fa163e000003fa163e00000186dd
+packet_l3=6000000000603afffe80000000000000f8163efffe000001fe80000000000000f8163efffe000003
+mtu_opt=05010000000005aa
+new_prefix_opt=030440c000002a3000002a3000000000fdad9abc0def00000000000000000000
+ra_packet=$packet_l2$packet_l3$packet_l4_hd_no_csum$sll_opt$mtu_opt$prefix_opt$new_prefix_opt
+
+as hv1 ovs-appctl netdev-dummy/receive vif2 $rs_packet
+echo $ra_packet | trim_zeros >> 2.expected
+
+sleep 1
+
+echo "------ hv1 dump ------"
+as hv1 ovs-vsctl show
+as hv1 ovs-ofctl -O OpenFlow13 show br-int
+as hv1 ovs-ofctl -O OpenFlow13 dump-flows br-int
+
+for i in 1 2; do
+    file=hv1/vif$i-tx.pcap
+    echo $file
+    # Remove checksum to compare.
+    $PYTHON "$top_srcdir/utilities/ovs-pcap.in" $file | trim_zeros | cut -b 1-112,117- > $i.packets
+    cat $i.expected > expout
+    AT_CHECK([cat $i.packets], [0], [expout])
+done
+
+OVN_CLEANUP([hv1])
+
+AT_CLEANUP
