[Pacemaker] ifstatus OCF RA

[Dejan Muhamedagic]

Hi,

On Tue, Feb 22, 2011 at 07:34:04AM +0200, Vladislav Bogdanov wrote:
> Hi,
> 21.02.2011 22:29, Florian Haas wrote:
> > On 02/21/2011 08:00 PM, Frederik Schüler wrote:
> >> Hello *,
> >>
> >> as the various ocf:*:ping[d] incarnations don't meet my specific needs,
> > 
> > May I ask why and how?
> 
> I was thinking about writing something similar. I need this in a quite
> complex networking setup, where one 10Gb iface and bonding on two 1Gbps
> ifaces are both members of a STP-enabled bridge. 10G is a preferred STP
> path. Cluster exports iSCSI luns backed by DRBD. What I need is to
> prefer node which has 10G path working for such exports. pingd is unable
> to help here. Although for my needs simple link status is not enough, I
> need to look at STP information too, this RA (didn't look at code yet)
> should be a good starting point for me.

Where can you get STP stuff from? How to interpret it? And then
how do you know it's something that won't change within next five
minutes? Finally, every failover can incur downtime, is it worth
the trouble because what you want is just more performance?
Perhaps you don't even need the extra performance at the time.
Other than that it sounds interesting :-)

> >> I 
> >> wrote a small RA using ethtool to detect a network link failure, in order to 
> >> trigger a failover.
> > 
> > Well, what if the link is up but there's an upstream problem? I've
> > always liked how ocf:pacemaker:ping actually monitors connectivity to an
> > upstream IP, which covers both immediate link failure and upstream
> > problems. Similar to how in active/backup bonding, you can fail over
> > based on the status of an ARP request, rather than MII link status.
> 
> Two RA's could be combined, we can have two location constraints with
> different attributes, no?

Sure.

Thanks,

Dejan

> Best,
> Vladislav
> 
> _______________________________________________
> Pacemaker mailing list: Pacemaker at oss.clusterlabs.org
> http://oss.clusterlabs.org/mailman/listinfo/pacemaker
> 
> Project Home: http://www.clusterlabs.org
> Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
> Bugs: http://developerbugs.linux-foundation.org/enter_bug.cgi?product=Pacemaker