Unusable hastd in FreeBSD 8.2

[Mikolaj Golub]

Hi,

On Mon, 6 Jun 2011 16:46:55 +0200 Victor Balada Diaz wrote:

 VBD> Hello,

 VBD> Hastd in it's current form is not usable on FreeBSD 8.2-RELEASE or in 8-STABLE. You
 VBD> can see why in this thread:

 VBD> http://lists.freebsd.org/pipermail/freebsd-fs/2011-February/010752.html

 VBD> You can see the committed fix in:

 VBD> http://svnweb.freebsd.org/base?view=revision&revision=219721

 VBD> But it's never been MFCd. Is it possible to MFC it to 8-STABLE and maybe
 VBD> do an errata notice for RELENG_8_2?

Actually, it was MFCed. In r220151.

Also, I don't think this is an issue that makes hastd unusable in FreeBSD 8.2 :-).

The issue is the following. Before switching the node to primary the failover
(third-party) script is checking if secondary process is still alive (assuming
that in this case the primary on another node is still alive too) and fails if
it is -- some protection against split brain.  But before r219721 secondary
might not die automatically when primary host was down.

This can be workarounded. E.g. by removing the check in the script :-). Or
setting net.inet.tcp.keepidle to some small value (e.g. 10 seconds) -- this
should make secondary notice that another end is dead after this interval.

-- 
Mikolaj Golub