Try dig. I haven't used it much, admittedly (so someone correct me if I'm wrong) but it will give you TTL (time-to-live) stats on DNS queries.
This showed my local cache (I think): [EMAIL PROTECTED]:~$ dig google.com ; <<>> DiG 9.3.1 <<>> google.com ;; global options: printcmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 41396 ;; flags: qr rd ra; QUERY: 1, ANSWER: 3, AUTHORITY: 0, ADDITIONAL: 0 ;; QUESTION SECTION: ;google.com. IN A ;; ANSWER SECTION: google.com. 65 IN A 64.233.187.99 google.com. 65 IN A 64.233.167.99 google.com. 65 IN A 72.14.207.99 ;; Query time: 1 msec ;; SERVER: 127.0.0.1#53(127.0.0.1) ;; WHEN: Wed Feb 1 15:05:29 2006 ;; MSG SIZE rcvd: 76 Then I tried this to see a name-server cache: [EMAIL PROTECTED]:~$ dig @128.223.32.35 google.com ; <<>> DiG 9.3.1 <<>> @128.223.32.35 google.com ; (1 server found) ;; global options: printcmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 23581 ;; flags: qr rd ra; QUERY: 1, ANSWER: 3, AUTHORITY: 4, ADDITIONAL: 4 ;; QUESTION SECTION: ;google.com. IN A ;; ANSWER SECTION: google.com. 44 IN A 72.14.207.99 google.com. 44 IN A 64.233.167.99 google.com. 44 IN A 64.233.187.99 ;; AUTHORITY SECTION: google.com. 345497 IN NS ns1.google.com. google.com. 345497 IN NS ns2.google.com. google.com. 345497 IN NS ns3.google.com. google.com. 345497 IN NS ns4.google.com. ;; ADDITIONAL SECTION: ns1.google.com. 338454 IN A 216.239.32.10 ns2.google.com. 338454 IN A 216.239.34.10 ns3.google.com. 338454 IN A 216.239.36.10 ns4.google.com. 338454 IN A 216.239.38.10 ;; Query time: 21 msec ;; SERVER: 128.223.32.35#53(128.223.32.35) ;; WHEN: Wed Feb 1 15:05:51 2006 ;; MSG SIZE rcvd: 212 If it can't find it, the TTL section will be blank: [EMAIL PROTECTED]:~$ dig @128.223.32.35 noexistano.google.com ; <<>> DiG 9.3.1 <<>> @128.223.32.35 noexistano.google.com ; (1 server found) ;; global options: printcmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 39264 ;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0 ;; QUESTION SECTION: ;noexistano.google.com. IN A ;; AUTHORITY SECTION: google.com. 60 IN SOA ns1.google.com. dns-admin.google.com. 2006013005 7200 1800 1038800 60 ;; Query time: 26 msec ;; SERVER: 128.223.32.35#53(128.223.32.35) ;; WHEN: Wed Feb 1 15:07:06 2006 ;; MSG SIZE rcvd: 89 Jason LaPier Network Manager TACS / WRRC University of Oregon # Captain's Log: http://jubunt.uoregon.edu > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Darren Hayes > Sent: Wednesday, February 01, 2006 2:42 PM > To: Eugene Unix and Gnu/Linux User Group > Subject: [Eug-lug] Is it DNS Caching? > > I have a website running on a vhost account (Apache 1.3.24/PHP4.4.1) > > I can get to http://www.domainname.com/index.html just fine I > can get to http://domainname.com/index.html just fine. > I can get to http://domainname.com/subdir/index.php just fine. > > I can get to http://www.domainname.com/blah.php just fine. > > But I observe the following 404 error when accessing > http://domainname.com/blah.php (note no "www" prefix) > > Not Found > The requested URL /blah.php was not found on this server. > Additionally, a 404 Not Found error was encountered while trying > to use an ErrorDocument to handle the request. > > NOTE: blah.php is a brand new file copied to the webroot by > the system admin this morning. > > I observe same issue on two different PC's. I've > reinitialized and rebooted everything in my neighborhood > (PC's, router, cable modem). I have flushed my DNS cache on > both PC and router. I have even flushed my toilet. > > System admin states he can get to > http://domainname.com/blah.php and states my issue is 99.9% > likely a DNS caching error and I should contact my ISP > (Comcast). Usually the guy is spot on, but this time I don't know. > > Any thoughts? > > Darren > > > > > > _______________________________________________ > EUGLUG mailing list > [email protected] > http://www.euglug.org/mailman/listinfo/euglug > _______________________________________________ EUGLUG mailing list [email protected] http://www.euglug.org/mailman/listinfo/euglug
