[PATCH] ctdb-takeover: Do not call ctdb_announce_vnn_iface() for updateip

Amitay Isaacs amitay at gmail.com
Thu Aug 10 04:44:40 UTC 2017

On Wed, Aug 9, 2017 at 4:55 PM, Martin Schwenke via samba-technical <
samba-technical at lists.samba.org> wrote:

> [I came across this when auditing code during my (unfinished)
>  connection tracking rewrite.]
> This causes any tracked connections for the IP address to be lost.
> When doing a takeip, the server sends a tickle ACK to the client, the
> client responds with a valid ACK and the server's TCP stack responds
> with a reset because the connection does not exist.  However, in the
> updateip, case the connection *does* exist, so the tickle *does not*
> cause the connection to be reset.
> ctdb_announce_vnn_iface() clears the list of tracked TCP connections
> while sending the tickle ACKs.  So, if there are no reconnects as in
> the takeip case, then the list of connections is simply lost.
> The "updateip" event in the 10.interface event script already sends
> gratuitous ARPs and tickles connections in both directions.  This
> ensures that traffic continues after packets may have been dropped
> when the script temporarily blocks traffic to the IP address.
> All of this means that the call to ctdb_announce_vnn_iface() can just
> be deleted.
> Please review and maybe push...
> peace & happiness,
> martin

Pushed to autobuild.


More information about the samba-technical mailing list