From owner-freebsd-current@FreeBSD.ORG Mon Jul 18 20:06:47 2005 Return-Path: X-Original-To: freebsd-current@freebsd.org Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id DDFD616A41C for ; Mon, 18 Jul 2005 20:06:47 +0000 (GMT) (envelope-from oberman@es.net) Received: from postal2.es.net (postal2.es.net [198.128.3.206]) by mx1.FreeBSD.org (Postfix) with ESMTP id 74CAB43D45 for ; Mon, 18 Jul 2005 20:06:47 +0000 (GMT) (envelope-from oberman@es.net) Received: from ptavv.es.net ([198.128.4.29]) by postal2.es.net (Postal Node 2) with ESMTP (SSL) id IBA74465; Mon, 18 Jul 2005 13:06:45 -0700 Received: from ptavv (localhost [127.0.0.1]) by ptavv.es.net (Tachyon Server) with ESMTP id AD5BF5D07; Mon, 18 Jul 2005 13:06:45 -0700 (PDT) To: Sam Leffler In-reply-to: Your message of "Fri, 15 Jul 2005 08:23:18 PDT." <42D7D4E6.3020105@errno.com> Date: Mon, 18 Jul 2005 13:06:45 -0700 From: "Kevin Oberman" Message-Id: <20050718200645.AD5BF5D07@ptavv.es.net> Cc: Randy Bush , freebsd-current@freebsd.org Subject: Re: Problems with OpenBSD dhclient X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 18 Jul 2005 20:06:48 -0000 > Date: Fri, 15 Jul 2005 08:23:18 -0700 > From: Sam Leffler > > Randy Bush 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! > >> > >>This should not be happening; dhclient should get a disassociate event, > >>drop the lease, then get an associate when you join the new ap and > >>immediately grab a new lease. > > > > > > aiii! this was merely a layer-2 re-association, no change at layer-3. > > I mis-spoke; dhclient trys to re-acquire the current lease. This is > exactly what happened before except it should now happen _immediately_ > on being notified of a re-association to the same ap or an association > to a new ap. Actually I could check for a re-association and not > re-aquire the lease to reduce the overhead but regardless this should be > ok (so far as I understand the protocols). > > The previous code polled for these events. This made it prone to > missing fast re-associations (instead falling back to various timeouts) > and slow to respond when roaming. The new code had been working > correctly; something has clearly changed and I'll fix it asap. I'm in Vancouver at a conference and my dhclient has been dying every few minutes. The room has 4 APs and I suspect the association is moving between them periodically. That is just a guess, though. In any case, several times an hour my IP address changes to 0.0.0.0 and then disappears completely. I still see the NIC associated with the same SSID and the signal quality is consistently excellent. Executing 'dhclient wi0' gets my connection back with the same IP address, so my SSH session survive as long as I restart the client fairly promptly when it goes away, but I have to watch closely. I'm now running 80211watch and I only see: Mon Jul 18 12:11:29 RTM_IEEE80211: disassociate Mon Jul 18 12:12:17 RTM_IEEE80211: disassociate Mon Jul 18 12:49:17 RTM_IEEE80211: disassociate Mon Jul 18 12:49:52 RTM_IEEE80211: disassociate These are interesting in that the first message occurs at some unknown time. The second seems to occur when dhclient is re-started. I don't understand why I never see an associate or reassociate event. Seems odd. In any case, this is a very annoying problem and I'd be happy th help as much as I can, but I'm trying to keep involved with the program at the same time. -- R. Kevin Oberman, Network Engineer Energy Sciences Network (ESnet) Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab) E-mail: oberman@es.net Phone: +1 510 486-8634