[ovs-dev,branch2.11] ovsdb-server: drop all connections on read/write status change

Prior to this patch, only db change aware connections were dropped
on a read/write status change. However, current schema in OVN does
not allow clients to monitor whether a particular DB changes this
status. In order to accomplish this, we'd need to change the schema
and adapting ovsdb-server and existing clients.

Before tackling that, this patch is changing ovsdb-server to drop
*all* the existing connections upon a read/write status change. This
will force clients to reconnect and honor the change.

Reported-at: https://mail.openvswitch.org/pipermail/ovs-discuss/2019-July/048981.html
Signed-off-by: Daniel Alvarez <dalvarez@redhat.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
---
 ovsdb/jsonrpc-server.c |  2 +-
 tests/ovn.at           | 21 +++++++++++++++++++++
 2 files changed, 22 insertions(+), 1 deletion(-)

--

On Fri, Jul 12, 2019 at 4:17 PM Daniel Alvarez <dalvarez@redhat.com> wrote:
>
> Prior to this patch, only db change aware connections were dropped
> on a read/write status change. However, current schema in OVN does
> not allow clients to monitor whether a particular DB changes this
> status. In order to accomplish this, we'd need to change the schema
> and adapting ovsdb-server and existing clients.
>
> Before tackling that, this patch is changing ovsdb-server to drop
> *all* the existing connections upon a read/write status change. This
> will force clients to reconnect and honor the change.
>
> Reported-at: https://mail.openvswitch.org/pipermail/ovs-discuss/2019-July/048981.html
> Signed-off-by: Daniel Alvarez <dalvarez@redhat.com>
> Signed-off-by: Ben Pfaff <blp@ovn.org>
> ---
>  ovsdb/jsonrpc-server.c |  2 +-
>  tests/ovn.at           | 21 +++++++++++++++++++++
>  2 files changed, 22 insertions(+), 1 deletion(-)
>
> diff --git a/ovsdb/jsonrpc-server.c b/ovsdb/jsonrpc-server.c
> index 7c7a277f0..739e0e72e 100644
> --- a/ovsdb/jsonrpc-server.c
> +++ b/ovsdb/jsonrpc-server.c
> @@ -365,7 +365,7 @@ ovsdb_jsonrpc_server_set_read_only(struct ovsdb_jsonrpc_server *svr,
>  {
>      if (svr->read_only != read_only) {
>          svr->read_only = read_only;
> -        ovsdb_jsonrpc_server_reconnect(svr, false,
> +        ovsdb_jsonrpc_server_reconnect(svr, true,
>                                         xstrdup(read_only
>                                                 ? "making server read-only"
>                                                 : "making server read/write"));
> diff --git a/tests/ovn.at b/tests/ovn.at
> index 4b14720f3..291330b3b 100644
> --- a/tests/ovn.at
> +++ b/tests/ovn.at
> @@ -12090,3 +12090,24 @@ ovn-nbctl list logical_switch_port
>  ovn-nbctl list logical_router_port
>
>  AT_CLEANUP
> +
> +# Run ovn-nbctl in daemon mode, change to a backup database and verify that
> +# an insert operation is not allowed.
> +AT_SETUP([ovn -- can't write to a backup database server instance])
> +ovn_start
> +on_exit 'kill $(cat ovn-nbctl.pid)'
> +export OVN_NB_DAEMON=$(ovn-nbctl --pidfile --detach)
> +
> +AT_CHECK([ovn-nbctl ls-add sw0])
> +as ovn-nb
> +AT_CHECK([ovs-appctl -t ovsdb-server ovsdb-server/sync-status | grep active | wc -l], [0], [1
> +])
> +ovs-appctl -t ovsdb-server ovsdb-server/set-active-ovsdb-server tcp:192.0.2.2:6641
> +ovs-appctl -t ovsdb-server ovsdb-server/connect-active-ovsdb-server
> +AT_CHECK([ovs-appctl -t ovsdb-server ovsdb-server/sync-status | grep -c backup], [0], [1
> +])
> +AT_CHECK([ovn-nbctl ls-add sw1], [1], [ignore],
> +[ovn-nbctl: transaction error: {"details":"insert operation not allowed when database server is in read only mode","error":"not allowed"}
> +])
> +
> +AT_CLEANUP
> --
Sorry, disregard this patch. The test is failing, I'll try to take a
look ASAP (next week).
>

Bleep bloop.  Greetings Daniel Alvarez Sanchez, 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.


git-am:
Failed to merge in the changes.
Patch failed at 0001 ovsdb-server: drop all connections on read/write status change
The copy of the patch that failed is found in:
   /var/lib/jenkins/jobs/upstream_build_from_pw/workspace/.git/rebase-apply/patch
When you have resolved this problem, run "git am --resolved".
If you prefer to skip this patch, run "git am --skip" instead.
To restore the original branch and stop patching, run "git am --abort".


Please check this out.  If you feel there has been an error, please email aconole@bytheb.org

Thanks,
0-day Robot