slow "KVM Host" in EL6 ?

[Paul N]

On Thu, May 12, 2011 at 3:30 PM, Ben <bda20 at cam.ac.uk> wrote:
> On Thu, 12 May 2011, Dmitry Makovey wrote:
>
>> we have some weird problem with EL6 box which serves as a KVM host for 3
>> VMs currently. It shares the same interface with all 3 VMs (same network).
>> All works, except from time to time machine behaves very slow in console
>> (ok, SSH connection) and it happens only from time to time.
>> [...]
>
> It may be unconnected but I have a RHEL6 box which also occasionally has an
> issue with slow SSH connection.  By that I mean you type "ssh rhel6host",
> the password prompt comes up quickly, but after entering the password and
> hitting return there's a palpable delay (sometimes) before the prompt
> appears.  Not every time, but often.  Sometimes as long as four to five
> seconds.  A RHEL6 KVM guest I installed on it also has the same issue
> (sometimes).  I've run ssh with -vvv and sshd with -vvv and not seen
> anything untoward.  DNS is on the local LAN and reports no issues either.
> All connections are from RHEL5 hosts.  Just somtimes connection is... slow.
>


Hi,

I've seen the problem you've described when I have a bogus entry for
localhost (or an incorrect IP address for the server's FQDN) in
/etc/hosts. YYMV of course!

Paul