Subject: Re: [vserver] vmstat and vserver
From: Herbert Poetzl <herbert@13thfloor.at>
Date: Sun, 7 Jun 2009 00:15:07 +0200

On Thu, Jun 04, 2009 at 02:57:26PM -0400, John A. Sullivan III wrote:
> Hello, all. We are trying to run zimbra in a vserver. We have almost
> everything working but there are a few nasty problems remaining. 
> One of them is the statistics collector which wants to run vmstat.

which doesn't really make sense inside a guest, as the
vmstat would show the host wide information

> This fills the error logs with messages about needing to mount /proc;
> I assume this is because /proc/vmstat is not exposed to the vserver.

well, it is because a program (probably vmstat) implements
a broken heuristic to determine whether proc is mounted
or not ...

> I would imagine the solution is to add /proc/vmstat to vprocunhide. 
> Are there any caveats to doing that?

not from the system PoV, but it shows host information
on a guest, which is usually not what you want

> I was hoping to do this just for the one vserver but it looks like 
> it's an all or nothing approach.  

yep, patches are welcome :)

but you could work around that by using --bind mounts to
replace the unwanted entry in other guests ...

> What is the difference between making the entry in 
> /etc/vservers/.defaults/apps/vprocunhide and 
> /usr/lib64/util-vserver/defaults/vprocunhide-files?

the former will be kept over updates, where the latter
will be replaced by a new util-vserver version

btw, IMHO the best solution to this 'problem' would be to
make this thing configureable in zimbra, the second best to
write a dummy vmstat script/binary to avoid the vmstat

best,
Herbert

> Thanks - John
> -- 
> John A. Sullivan III
> Open Source Development Corporation
> +1 207-985-7880
> jsullivan@opensourcedevel.com
> 
> http://www.spiritualoutreach.com
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