Re: ipvs failback patch

[Ranga Nathan <kairanga@xxxxxxx>]

Horms wrote:

> Ranga Nathan <kairanga@xxxxxxx> wrote:
>  
>
> > Horms wrote:
> >
> >    
> >
> > > Ranga Nathan <kairanga@xxxxxxx> wrote:
> > >
> > >
> > >      
> > >
> > > > Karl Kopper's Linux Enterprise Cluster talks about the availability of  
> > > > a kernel patch to failback from the backup to the master that keeps the 
> > > > connections alive.
> > > > I could not find it on the linuxvirtualserver.org site. I see the latest 
> > > > versions but they are in source format. Somehow I am unable to do rpm 
> > > > --rebuild <sourcerpm>
> > > > The current version I have is: ipvsadm v1.24 2003/06/07 (compiled with 
> > > > getopt_long and IPVS v1.2.0)
> > > >   
> > > >
> > > >        
> > > Could you be a little more specific about the patch
> > > (or at least give a page refernce in the book).
> > >
> > >
> > >      
> > It is the NOTE at the bottom of p276 (Stateful Failover of the IPVS Table)
> >
> >    
> >
> > > I am suspecting that this patch is no longer needed.
> > >
> > >
> > >      
> > When it fails over, the connections are retained. When it fails back, 
> > the connections are broken.
> > I simulated this by rebooting (this is my lab machine!)  the directors.
> >    
> Ok, I'm still a little confused, but I think what he is talking
> about is being able to run the master and backup daemons on
> both linux-directors at the same time. That patch was merged
> into the kernel a while ago now, and the chances are that
> you can do this without patching. To test, try running:
>
> ipvsadm --start-daemon master
> ipvsadm --start-daemon backup
>  
I am sorry, I did not explain very well. My language is not very 
technical :-) I did  what you suggested before. From master to backup 
the failover worked fine. I did not lose any connections. From backup, 
when the master (after a reboot) snatched back the nodes, the 
connections dropped.  I am sure that when the master came backup, it 
started the daemon, as I had "--start-daemon master" in the 
/etc/ipvsadm.rules. I confirmed this by doing "ipvsadm --start-daemon 
master" on the master and it said "Daemon has already run".  I could not 
query if it is in "master" status. I presumed so.
I there a way for the master and backup swap dynamically when snatching 
the nodes?
> Which if it works, will improve things somewhat.
>
>