[CentOS] Replacement for Linux-HA (heartbeat) - RedHat cluster?

Fri Nov 30 23:41:09 UTC 2007
Matt Shields <mattboston at gmail.com>

On Nov 30, 2007 6:40 PM, Matt Shields <mattboston at gmail.com> wrote:
>
> On Nov 30, 2007 6:28 PM, Amos Shapira <amos.shapira at gmail.com> wrote:
> > On 30/11/2007, Matt Shields <mattboston at gmail.com> wrote:
> > > LVS is a group of tools that do a lot of different things, the two
> > > that you are interested in are:
> > >
> > > - heartbeat - provides failover if you have two nodes (active/active
> > > or active/passive)
> > > - ipvsadm/ldirectord - provides load balancing (ie. http(s) load
> > > balancer in front of multiple web servers)
> > >
> > > As stated in a previous post we have a number of these setup in our
> > > network and we handle a lot of traffic.  Some we're using for http(s)
> > > traffic, others smtp/pop/imap, others mysql (read only queries off
> > > replicas).  There's no end to what what you could use heartbeat or
> > > ipvsadm/ldirectord or both for.  Both packages can be installed from
> > > dag's repo.
> >
> > Thanks.
> >
> > What platform are you using? Mine is CentOS 5 on x86_64. It runs as a
> > Xen DomU but from what I read on the linux-ha users mailing list this
> > shouldn't be the issue. The production system will run on the bare
> > metal (not under Xen).
> >
> > My experience with LVS at a previous workplace (a very large ISP) was
> > also excellent - they had a couple of LVS servers in front of hundreds
> > of mini-clusters (each such cluster service its own web or other
> > network application, sometimes sharing disks using DRBD).
> >
> > The difference, I suspect, is that I'm trying this now with version
> > 2.1.2 on CentOS 5 and x86_64, as opposed to possibly older version of
> > everything (RedHat version, LVS, hardware (i386)).
> >
> > Thanks for your input,
>
> Take Xen out of the picture until you learn how heartbeat and
> ipvsadm/ldirectord actually work.  You could be having network issues
> because you are hosting it on a virtual server instead of on a real
> server.  So it's kinda hard to troubleshoot if you don't even know if
> your configs are broken.  Get two crappy boxes that you can load
> everything up on, configure them with heartbeat, get that working
> where it will failover an IP.  then add some other service like
> ipvsadm/ldirectord, and take things one step at a time.  Don't try to
> setup everything all at once, it makes it harder to try to debug
> problems.
>
> I'm using CentOS4 and RHEL4 using dag'd rpms on a few of the CentOS
> and RHEL boxes and built from source on some of the other ones.  I
> haven't had a chance to try out a CentOS 5 system yet.  But as to your
> stability questions, we've been using LVS for about 3 or 4 years now
> and never, ever had stability problems.
>

Also, we're on a mix of i386 and x86_64 systems.  But for each cluster
the pair of nodes is identicle.


-- 
-matt