From owner-freebsd-questions@FreeBSD.ORG Thu Jan 19 15:16:06 2012 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 F1798106566B for ; Thu, 19 Jan 2012 15:16:05 +0000 (UTC) (envelope-from ndhertbsd@gmail.com) Received: from mail-gx0-f182.google.com (mail-gx0-f182.google.com [209.85.161.182]) by mx1.freebsd.org (Postfix) with ESMTP id AB1018FC08 for ; Thu, 19 Jan 2012 15:16:05 +0000 (UTC) Received: by ggki1 with SMTP id i1so29307ggk.13 for ; Thu, 19 Jan 2012 07:16:05 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=5vmJJ6VmPbKpmrjhjyIkB4kdc9GtZB8NNUQXhaTWYV8=; b=bV6zyHV26zruQE/Y49Xs3KvTI2gaDn4QEsFVrkEZN4uJeiPT/TDrXHwDphLOjJDOnc bg0Tyzn4V9dglb+O3Zw4PD/XRrS5E0gVQFzobziBTOLIVkceKDEp6eJnad2N/htuNNB/ HjoRt/dx4fkVwwQNiHqy8/bv4ODfUt1DP0qJo= MIME-Version: 1.0 Received: by 10.50.182.199 with SMTP id eg7mr25445954igc.22.1326986163362; Thu, 19 Jan 2012 07:16:03 -0800 (PST) Received: by 10.42.158.65 with HTTP; Thu, 19 Jan 2012 07:16:03 -0800 (PST) In-Reply-To: References: <4F182A5A.30202@my.gd> Date: Thu, 19 Jan 2012 16:16:03 +0100 Message-ID: From: n dhert To: freebsd-questions@freebsd.org Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Subject: Re: changed ip-adress, DNS lookups don't work anymore 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, 19 Jan 2012 15:16:06 -0000 > > - with UseDNS no, I can login quickly again.. > - I don't manage the DNS servers, can do anything there, but I do believe > they do not receive anything > since I now see, I can't even ping any of the three of tehm, specified in > my /etc/resolv,conf file > # ping 143.169.254.100 > - the /etc/resolv.conf file is OK (same as on other machines getting DHCP > info from the same DHCP server) > > [admin@pclinwi7475old 75.126 ~]$ netstat -m > 258/267/525 mbufs in use (current/cache/total) > 256/134/390/16704 mbuf clusters in use (current/cache/total/max) > 256/128 mbuf+clusters out of packet secondary zone in use (current/cache) > 0/2/2/8352 4k (page size) jumbo clusters in use (current/cache/total/max) > 0/0/0/4176 9k jumbo clusters in use (current/cache/total/max) > 0/0/0/2088 16k jumbo clusters in use (current/cache/total/max) > 576K/342K/919K bytes allocated to network (current/cache/total) > 0/0/0 requests for mbufs denied (mbufs/clusters/mbuf+clusters) > 0/0/0 requests for jumbo clusters denied (4k/9k/16k) > 0/4/4432 sfbufs in use (current/peak/max) > 0 requests for sfbufs denied > 0 requests for sfbufs delayed > 0 requests for I/O initiated by sendfile > 0 calls to protocol drain routines > [admin@pclinwi7475old 75.126 ~]$ ifconfig > em0: flags=8843 metric 0 mtu 1500 > > options=209b > ether 00:0b:db:53:3e:15 > inet 143.129.75.126 netmask 0xffffff00 broadcast 143.129.75.255 > media: Ethernet autoselect (100baseTX ) > status: active > plip0: flags=8810 metric 0 mtu 1500 > lo0: flags=8049 metric 0 mtu 16384 > options=3 > inet6 fe80::1%lo0 prefixlen 64 scopeid 0x3 > inet6 ::1 prefixlen 128 > inet 127.0.0.1 netmask 0xff000000 > nd6 options=3 > I'm believing now there is still something wrong on the firewall > something in the cache referring to the old IP address ??? > > I use shorewall on a Ubuntu 11.04 ... > > > 2012/1/19 Damien Fleuriot > >> >> >> On 1/19/12 3:32 PM, n dhert wrote: >> > FreeBSD 8.2. system. >> > Gets is TCP/IP parameters (and DNS name-servers IPs) from a DHCP server, >> > with a fixed IP address >> > (the system always gets the same IP, based on its MAC address as >> specified >> > in the DHCP config file) >> > >> > Now I wanted the system to have a different IP address. >> > Changed the DHCP server config accordingly. >> > Reboot. OK, from $ ifconfig -a I can see it received the new IP. >> > >> > But DNS lookups don't work any longer .. >> > $ host xxx.yyy.zzz.com >> > ;; connection timed out; no servers could be reached >> > >> > The system is behind a firewall, but there are NO errors logged relating >> > to the (new) IP address. >> > Other FreeBSD-8.2 systems using the same DHCP server, configured in >> exactly >> > the same way, work perfectly well. >> > >> > I can SSH to the sytem, but it takes 20 or 30 seconds before the >> Password: >> > prompt appears (normally should >> > be immediate) >> > Once in the system, starting my alpine mail-client, it takes a minute >> or so >> > to display the messages (normally this should be immediate) >> > Also at boot of the system there is wait for a 2,5 minutes somewhere in >> the >> > series of Starting . >> > Probably these three phenomena have the same cause: DNS lookups don't >> work >> > >> > any idea what can be wrong ?? >> > I've looked and compared with other systems, can't find it ... >> > >> >> >> First, add "UseDNS no" to either /etc/ssh/sshd_config or >> /usr/local/etc/ssh/sshd_config >> >> That'll allow you to log in via SSH without the server performing DNS >> lookups, which are rather useless anyway. >> >> Second, you should run "tcpdump" on your DNS host to check if you're >> actually receiving requests from your freebsd box. >> >> >> Also, post your /etc/resolv.conf , "netstat -rn" and "ifconfig" >> >> I'd also be interested in the relevant parts of your firewalling config >> _______________________________________________ >> freebsd-questions@freebsd.org mailing list >> http://lists.freebsd.org/mailman/listinfo/freebsd-questions >> To unsubscribe, send any mail to " >> freebsd-questions-unsubscribe@freebsd.org" >> > >