Re: [Vserver] Host and guest compatability

From: Jim Wight <>
Date: Wed 09 Aug 2006 - 14:22:14 BST
Message-Id: <>

On Wed, 2006-08-09 at 08:17 +0200, Guenther Fuchs wrote:
> on Tuesday, August 8, 2006 at 9:46:04 PM there was posted:
> JW> To what extent do the host and the guest have to be compatible?
> Only to the kernel, no more, none else.

That's what I thought.

> JW> # vserver fc5 start
> JW> /usr/bin/env: /lib/ version `GLIBC_2.4' not found
> JW> (required by /usr/bin/env)
> Don't know where this comes from, but it definately relates _only_ to
> the guest.

> JW> FC5 has glibc 2.4 whereas FC4 has glibc 2.3. Is that really the
> JW> problem, or is the message a side-effect of some other problem?
> It is definately an effect of a guest related problem, which does
> _not_ relate to the hosts glibc.

Well, that's the error I get when I run /vservers/fc5/usr/bin/env on the
host. 'chroot /vservers/fc5 /usr/bin/env' is OK.

Maybe all my vservers behave the same way. It's difficult to tell
because in all cases the guest's /usr/bin/env runs on the host without
error. Just today I've upgraded some host machines to FC5 from FC4. They
were supporting FC2 vservers, which I've found still
run. /vservers/fc2/usr/bin/env runs without error on the FC5 host, so
I've no idea whether it is being executed on the host or in the guest
during vserver startup.

By adding 'set -x' to vserver.start I can see that the last output
before the error message is a long command, which appears to be a chain
of util-vserver commands separated by '--', . One of those (in essence)
is 'save_ctxinfo /etc/vservers/fc5 /usr/bin/env -i'.
>From looking at its source code, I deduce that it must be getting run in
the vserver's context otherwise it would fail with 'save_ctxinfo: Can
not operate in context 0". I'm guessing that that /usr/bin/env, whatever
is done with it, is the source of the problem - but I wouldn't know as
I'm not finding it the easiest thing in the world to make sense of what
the utils do.


Vserver mailing list
Received on Wed Aug 9 14:22:45 2006

[Next/Previous Months] [Main vserver Project Homepage] [Howto Subscribe/Unsubscribe] [Paul Sladen's vserver stuff]
Generated on Wed 09 Aug 2006 - 14:22:50 BST by hypermail 2.1.8