From owner-freebsd-questions@FreeBSD.ORG Thu Jun 4 20:27:20 2009 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 6A672106566C for ; Thu, 4 Jun 2009 20:27:20 +0000 (UTC) (envelope-from fbsdq@peterk.org) Received: from poshta.pknet.net (poshta.pknet.net [216.241.167.213]) by mx1.freebsd.org (Postfix) with SMTP id 2007F8FC12 for ; Thu, 4 Jun 2009 20:27:19 +0000 (UTC) (envelope-from fbsdq@peterk.org) Received: (qmail 44974 invoked from network); 4 Jun 2009 20:27:19 -0000 Received: from poshta.pknet.net (HELO pop.pknet.net) (216.241.167.213) by poshta.pknet.net with SMTP; 4 Jun 2009 20:27:19 -0000 Received: from 216.241.167.212 (SquirrelMail authenticated user fbsdq@peterk.org) by webmail.pknet.net with HTTP; Thu, 4 Jun 2009 14:27:19 -0600 (MDT) Message-ID: <5359c8a6e4fc10bf951a7ee095b0d29f.squirrel@webmail.pknet.net> Date: Thu, 4 Jun 2009 14:27:19 -0600 (MDT) From: "Peter" To: "Mel Flynn" User-Agent: SquirrelMail/1.4.17 MIME-Version: 1.0 Content-Type: text/plain;charset=iso-8859-1 Content-Transfer-Encoding: 8bit X-Priority: 3 (Normal) Importance: Normal Cc: Peter , freebsd-questions@freebsd.org Subject: Re: /etc/hosts - how does that file work?? - was weird nfs issues. X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 04 Jun 2009 20:27:20 -0000 > On Thursday 04 June 2009 20:48:21 Peter wrote: >> iH, >> This all started with NFS not mounting at boot....so, testing in VMs: > > > >> Why is ping using one IP, and ssh/mount_nfs/showmount using another IP from /etc/hosts? > > Q: Where is described that name resolution for A or PTR records should be > returned in a fixed order and that a consumer should always use the first > one > returned? > A: Nowhere. Name servers are encouraged to do round-robin returns if not specified otherwise. Applications may sort/pick at their own leisure. > > -- > Mel I do not think /etc/hosts does round robin, I always assumed first match wins...DNS/bind I would understand... Why does ping always return the 172.20.6.1 address, and ftp,nc,ssh,telnet,fetch _always_ uses the 116 address? I would assume at least sometimes it would hit the 172 address with anything besides ping - but it only ping hits the 172 address... If so, I'd guess there would be consistency between ping lookups and 'telnet/ssh/etc' lookups... Why if the 116.23.45.3 last octet is bumped up, everything _always_ returns the 172 address? client# grep server /etc/hosts 172.20.6.1 server.test server 116.23.45.5 server.test server client# telnet server Trying 172.20.6.1... telnet: connect to address 172.20.6.1: Connection refused Trying 116.23.45.5... /etc/hosts - 'server' changed to 116.23.45.3: client# telnet server Trying 116.23.45.3... telnet: connect to address 116.23.45.3: Operation timed out Trying 172.20.6.1... telnet: connect to address 172.20.6.1: Connection refused telnet: Unable to connect to remote host if server has ip>116.23.45.3, it always uses the 172 address first... but ping always uses the 172... even if third entry is added into /etc/hosts - nothing ever uses it as the first/primary IP. Is there an algorithm based on IP/program being used and the returned IP?