From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 21343 invoked by alias); 20 Jun 2007 21:46:13 -0000 Received: (qmail 21335 invoked by uid 22791); 20 Jun 2007 21:46:12 -0000 X-Spam-Check-By: sourceware.org Received: from londo.lunn.ch (HELO londo.lunn.ch) (80.238.139.98) by sourceware.org (qpsmtpd/0.31) with ESMTP; Wed, 20 Jun 2007 21:46:04 +0000 Received: from lunn by londo.lunn.ch with local (Exim 3.36 #1 (Debian)) id 1I17zz-0002X8-00; Wed, 20 Jun 2007 23:45:59 +0200 Date: Thu, 21 Jun 2007 15:07:00 -0000 To: Tad Cc: eCos Disuss Message-ID: <20070620214559.GB8424@lunn.ch> Mail-Followup-To: Tad , eCos Disuss References: <46783A66.4040503@ds3switch.com> <20070619192426.GF24842@lunn.ch> <4678630E.3050406@ds3switch.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4678630E.3050406@ds3switch.com> User-Agent: Mutt/1.5.13 (2006-08-11) From: Andrew Lunn X-IsSubscribed: yes Mailing-List: contact ecos-discuss-help@ecos.sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: ecos-discuss-owner@ecos.sourceware.org Subject: Re: [ECOS] Is arpresolve() good to get ARP started on an IP address? X-SW-Source: 2007-06/txt/msg00223.txt.bz2 On Tue, Jun 19, 2007 at 03:13:18PM -0800, Tad wrote: > Andrew Lunn wrote: > >On Tue, Jun 19, 2007 at 12:19:50PM -0800, Tad wrote: > > > >>SNMP agent is dropping coldstart and LinkUp traps since ARP table comes > >>up without entries > >> > > > >Maybe i don't understand what you are saying, but if there is no ARP > >entry, the IP packet which needs to be sent is normally queued and an > >ARP request is sent out. Once an ARP reply is received the queues > >packet is then sent. Is this not happening? > ARP will only que one mbuf, then drops it if more come in If a > coldstart and 2 link-up traps occur at powerup, and if we have 2 > trapsinks, for example, that's 6 msgs of which 4-5 are dropped. I need > to update the ipdropped snmp stats counter too, cause it took awhile to > figure out where the missing packets were going. Looked tricky to use > arpresolve? without dropping any mbuf queued there also. Ah, O.K. Well, two comments: SNMP is designed to be unreliable. It uses UDP. So this is acceptable behaviour. You could change the single mbuf into a queue. All the macros to do this exist, so i doubt it would be too big a job. Andrew -- Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss