Re: Problems with OpenBSD dhclient

On Thu, 14 Jul 2005, Kevin Oberman wrote:

> More serious is that I can't roam. When I move between APs, dhclient 
> exits and I need to manually re-start it. I lose my SSH sessions. Ugh!
>
> Worse, I occasionally see my association drop momentarily when I am 
> simply sitting and typing. Once again, dhclient dies and I must manually 
> restart it and then re-establish my SSH and recover anything broken when 
> the connection dropped. This is fairly serious! I don't understand what 
> causes this, but it is infrequent which makes it hard to catch.
>
> It looks like killing dhclient when the interface drops is not a good 
> idea. At very least, it needs to give a little time for re-association 
> before dropping the DHCP client.

I'm experiencing similar or identical problems.  When at the British 
Library the day before yesterday, slight blips in my association would 
result in loss of my IP address, requiring manual restarting of dhclient.

My normal approach for wireless/etc is to settle on a link -- be it wired 
ethernet or 802.11, and run dhclient on it to get things going.  When 
done, I'll typically kill off dhclient.  This worked pretty well with the 
old dhclient setup, but not so well with the new one.  Because I range 
over a variety of network environments, from adhoc 802.11, wired ethernet, 
to base station based 802.11, I tend to want to say "do this for now", and 
have it stick until I move on.  Maybe what I need to change is software 
configuration -- i.e., devd to re-launch dhclient.  But obviously what I'm 
doing now isn't working, and results in a pretty poor user experience 
(blips or roaming and suddenly the network is gone).

Robert N M Watson