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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 M.Blackmore wrote: > > Is the solution to the "looking up" time lag a local DNS cache? Whilst I run such boxes in a lot of places, I do it for reasons other than performance, although there can be a performance gain if you have the free memory to burn. If the ISP you use is unable to run a well performing DNS cache, you need a new ISP. But I doubt that is the problem. Get some timings for DNS lookups to see if they are slow. Repeatedly requesting the same lookup, should also show the effects of caching. Here for example I query "www.sun.com" twice in quick succession. srw@derek:~$ dig www.sun.com ; <<>> DiG 9.2.4 <<>> www.sun.com ;; global options: printcmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 17361 ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 4, ADDITIONAL: 0 ;; QUESTION SECTION: ;www.sun.com. IN A ;; ANSWER SECTION: www.sun.com. 3600 IN A 209.249.116.195 ;; AUTHORITY SECTION: sun.com. 86400 IN NS ns1.sun.com. sun.com. 86400 IN NS ns2.sun.com. sun.com. 86400 IN NS ns7.sun.com. sun.com. 86400 IN NS ns8.sun.com. ;; Query time: 792 msec ;; SERVER: 127.0.0.1#53(127.0.0.1) ;; WHEN: Mon Aug 1 17:30:08 2005 ;; MSG SIZE rcvd: 117 srw@derek:~$ dig www.sun.com ; <<>> DiG 9.2.4 <<>> www.sun.com ;; global options: printcmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 41196 ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 4, ADDITIONAL: 0 ;; QUESTION SECTION: ;www.sun.com. IN A ;; ANSWER SECTION: www.sun.com. 3584 IN A 209.249.116.195 ;; AUTHORITY SECTION: sun.com. 86384 IN NS ns1.sun.com. sun.com. 86384 IN NS ns2.sun.com. sun.com. 86384 IN NS ns7.sun.com. sun.com. 86384 IN NS ns8.sun.com. ;; Query time: 1 msec ;; SERVER: 127.0.0.1#53(127.0.0.1) ;; WHEN: Mon Aug 1 17:30:24 2005 ;; MSG SIZE rcvd: 117 First time it took 792 milliseconds, second time 1 msec (I'd expect maybe 10 to 30 milliseconds from a remote DNS server). So no problem there. Note it would probably have been quicker using Demon's DNS servers for the first lookup, as they no doubt have "www.sun.com" cached most of the time! So running your own server isn't guaranteed faster... It is possible there is some other DNS misconfiguration going on. Are the servers in /etc/resolv.conf all working, and all fast... Try for each IP address... dig @IP.AD.DR.ES www.sun.com Do you allow both TCP and UDP queries to the relevant DNS servers? Also DNS lookups can get very slow, if packets are being dropped due to congestion (or poorly implemented traffic shaping), as the retry times can be quite laid back (at least in systems that implement a sane retry policy - unlike recent versions of MS Windows that really don't try and play nicely with the other computers in the world). I suspect your slow starts may well be nothing to do with DNS. -----BEGIN PGP SIGNATURE----- Comment: Encryption...is a powerful defensive weapon for free people. Comment: Using GnuPG with Thunderbird - http://enigmail.mozdev.org iD8DBQFC7lFEGFXfHI9FVgYRAtD3AJ9rGlZn9OSqulyyc65GeYjuNhwp0ACcDTrE doCznS13UNvk5m/S4S3WMtY= =pw6k -----END PGP SIGNATURE----- -- The Mailing List for the Devon & Cornwall LUG Mail majordomo@xxxxxxxxxxxxx with "unsubscribe list" in the message body to unsubscribe. FAQ: www.dcglug.org.uk/linux_adm/list-faq.html