Sometimes users get host unknown

[Andrew Watkins]

one small typo in my original e-mail.

> Our webserver has many addresses
> www.lkl.ac.uk
> www.lonklab.ac.uk
> www.londonknowledge.ac.uk
                      ^lab missing....


   www.londonknowledgelab.ac.uk.

Some interesting replies which I am now checking.

Andrew

Andrew Watkins wrote:
> Hi,
> 
> We have had an ongoing problem that some people (over the world) that 
> they can not access our web server, since they do not get an IP address.
> 
> I have tested from my home ISP (away from work) and am unable to get the 
> same errors. I have tested the DNS from a few web sites www.dnsstuff.com 
> , etc and can not pin point any major problem
> 
> Our webserver has many addresses
> www.lkl.ac.uk
> www.lonklab.ac.uk
> www.londonknowledge.ac.uk
> 
> 
> The last report we had from a user was: dig +trace +qr www.lkl.ac.uk
> 
> ; <<>> DiG 9.2.1 <<>> +trace +qr www.lkl.ac.uk
> ;; global options:  printcmd
> .                       47891   IN      NS      c.root-servers.net.
> .                       47891   IN      NS      b.root-servers.net.
> ;; Received 356 bytes from 165.225.198.2#53(165.225.198.2) in 5 ms
> 
> uk.                     172800  IN      NS      NS1.NIC.uk.
> uk.                     172800  IN      NS      NSD.NIC.uk.
> ;; Received 493 bytes from 192.33.4.12#53(c.root-servers.net) in 48 ms
> 
> ac.uk.                  172800  IN      NS      ns1.cs.ucl.ac.uk.
> ac.uk.                  172800  IN      NS      ns2.ja.net.
> ac.uk.                  172800  IN      NS      ns3.ja.net.
> ac.uk.                  172800  IN      NS      ns4.ja.net.
> ac.uk.                  172800  IN      NS      sunic.sunet.se.
> ac.uk.                  172800  IN      NS      ws-fra1.win-ip.dfn.de.
> ac.uk.                  172800  IN      NS      ns.uu.net.
> ac.uk.                  172800  IN      NS      ns0.ja.net.
> ;; Received 233 bytes from 195.66.240.130#53(NS1.NIC.uk) in 129 ms
> 
> lkl.ac.uk.              86400   IN      NS      ns1.lonklab.ac.uk.
> lkl.ac.uk.              86400   IN      NS      mail1.ccs.bbk.ac.uk.
> ;; Received 101 bytes from 128.16.5.32#53(ns1.cs.ucl.ac.uk) in 150 ms
> 
> dig: Couldn't find server 'ns1.lonklab.ac.uk': Name or service not known
> 
> 
> Any pointers?
> 
> 
> Thanks in advance,
> 
> Andrew Watkins
> *****************************************************************************
> Unix Administrator                           tel: 020-7631 6720
> Computer Science Department                  fax: 020-7631 6727
> Birkbeck College (University of London)
> Malet Street
> London                                       e-mail: andrew at dcs.bbk.ac.uk
> WC1E 7HX 
> http://www.dcs.bbk.ac.uk/~andrew
> *****************************************************************************
> 
> 
>