diff mbox series

[ovs-dev,v2] ovn-sb.ovsschema: Avoid duplicated IPs in Encap table.

Message ID 1542137159-73672-1-git-send-email-hzhou8@ebay.com
State Superseded
Headers show
Series [ovs-dev,v2] ovn-sb.ovsschema: Avoid duplicated IPs in Encap table. | expand

Commit Message

Han Zhou Nov. 13, 2018, 7:25 p.m. UTC 
From: Han Zhou <hzhou8@ebay.com>

When adding a new chassis, if there is an old chassis with same IP
existed in Encap table, it is allowed to be added today. However,
allowing it to be added results in problems:

1. The new chassis cannot work because none of the other chassises
   are able to create tunnel to it, because of the IP confliction
   with already existed tunnel to the old chassis.

2. All the other chassises will continuously retry creating the tunnel
   and complaining about the error.

So, instead of hiding the problem, it is better to expose it while
trying to add the second chassis with duplicated IP. This patch
ensures it from the ovsdb schema.

Signed-off-by: Han Zhou <hzhou8@ebay.com>
---
 ovn/ovn-sb.ovsschema | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

Comments

Ben Pfaff Nov. 15, 2018, 5:24 p.m. UTC | #1 
On Tue, Nov 13, 2018 at 11:25:59AM -0800, Han Zhou wrote:
> From: Han Zhou <hzhou8@ebay.com>
> 
> When adding a new chassis, if there is an old chassis with same IP
> existed in Encap table, it is allowed to be added today. However,
> allowing it to be added results in problems:
> 
> 1. The new chassis cannot work because none of the other chassises
>    are able to create tunnel to it, because of the IP confliction
>    with already existed tunnel to the old chassis.
> 
> 2. All the other chassises will continuously retry creating the tunnel
>    and complaining about the error.
> 
> So, instead of hiding the problem, it is better to expose it while
> trying to add the second chassis with duplicated IP. This patch
> ensures it from the ovsdb schema.
> 
> Signed-off-by: Han Zhou <hzhou8@ebay.com>

I'm worried that this will make it hard for users to upgrade: if they
have any duplicate chassis, then they will have to manually delete them
before ovsdb-server will accept the new database.

I think you mentioned that ovn-controller can't delete the duplicates
because of RBAC permissions.  What if ovn-northd deletes them instead?
If it doesn't have a way to know which one is the "correct" one, it
could just delete all of the duplicates, since the ovn-controller that
is actually running will re-create its chassis if it disappears.
Han Zhou Nov. 15, 2018, 7:09 p.m. UTC | #2 
On Thu, Nov 15, 2018 at 9:24 AM Ben Pfaff <blp@ovn.org> wrote:
>
> On Tue, Nov 13, 2018 at 11:25:59AM -0800, Han Zhou wrote:
> > From: Han Zhou <hzhou8@ebay.com>
> >
> > When adding a new chassis, if there is an old chassis with same IP
> > existed in Encap table, it is allowed to be added today. However,
> > allowing it to be added results in problems:
> >
> > 1. The new chassis cannot work because none of the other chassises
> >    are able to create tunnel to it, because of the IP confliction
> >    with already existed tunnel to the old chassis.
> >
> > 2. All the other chassises will continuously retry creating the tunnel
> >    and complaining about the error.
> >
> > So, instead of hiding the problem, it is better to expose it while
> > trying to add the second chassis with duplicated IP. This patch
> > ensures it from the ovsdb schema.
> >
> > Signed-off-by: Han Zhou <hzhou8@ebay.com>
>
> I'm worried that this will make it hard for users to upgrade: if they
> have any duplicate chassis, then they will have to manually delete them
> before ovsdb-server will accept the new database.
>
> I think you mentioned that ovn-controller can't delete the duplicates
> because of RBAC permissions.  What if ovn-northd deletes them instead?
> If it doesn't have a way to know which one is the "correct" one, it
> could just delete all of the duplicates, since the ovn-controller that
> is actually running will re-create its chassis if it disappears.

Hi Ben, as discussed in today's meeting, I sent v3 with NEWS updated.
https://mail.openvswitch.org/pipermail/ovs-dev/2018-November/353973.html
diff mbox series

Patch

diff --git a/ovn/ovn-sb.ovsschema b/ovn/ovn-sb.ovsschema
index 5b9537f..afa9859 100644
--- a/ovn/ovn-sb.ovsschema
+++ b/ovn/ovn-sb.ovsschema
@@ -1,7 +1,7 @@ 
 {
     "name": "OVN_Southbound",
-    "version": "1.17.0",
-    "cksum": "3217981733 15045",
+    "version": "1.18.0",
+    "cksum": "910560265 15086",
     "tables": {
         "SB_Global": {
             "columns": {
@@ -50,7 +50,8 @@ 
                                      "min": 0,
                                      "max": "unlimited"}},
                 "ip": {"type": "string"},
-                "chassis_name": {"type": "string"}}},
+                "chassis_name": {"type": "string"}},
+            "indexes": [["type", "ip"]]},
         "Address_Set": {
             "columns": {
                 "name": {"type": "string"},