There are some anomalies on a Virtuozzo virtualized Debian 4 (I know, I'm gonna upgrade this one asap, but there dependences). We run some Websites on this one. And a view Days ago exmi4 wasnt able to send mails to SOME people. I'll use live.com as exampledomain!
So some of this people got mails and some didn't.
Some of the mails got stuck in the queue, and after 2 days they went out!!
My Nagios never showed problems with the internet connection or disk space
Now i wanted to install "dig" to look how he's solving the dns request. And this Debian tells me he doesn't know dig..
Long story made short, Debian is able to download sites with exact IP or even with wget live.com, but it is not able to ping live.com.
I'm 99% sure that the networking is right and the routing too!
Some examples of my tring below:
downloads the site
ping live.com ping http://www.live.com ping http://live.com
ping: unknown host live.com
i now use heise.de not live.com any more.
and i found out i can ping the heise.de server by using it's IP-address.
myserver:~# ping 188.8.131.52 PING 184.108.40.206 (220.127.116.11) 56(84) bytes of data. 64 bytes from 18.104.22.168: icmp_seq=1 ttl=248 time=12.7 ms 64 bytes from 22.214.171.124: icmp_seq=2 ttl=248 time=12.6 ms 64 bytes from 126.96.36.199: icmp_seq=3 ttl=248 time=12.9 ms 64 bytes from 188.8.131.52: icmp_seq=4 ttl=248 time=13.1 ms 64 bytes from 184.108.40.206: icmp_seq=5 ttl=248 time=13.1 ms --- 220.127.116.11 ping statistics --- 5 packets transmitted, 5 received, 0% packet loss, time 4001ms rtt min/avg/max/mdev = 12.671/12.924/13.163/0.238 ms
myserver:/etc/apt# dig heise.de ; <<>> DiG 9.3.4-P1.2 <<>> heise.de ;; global options: printcmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 40551 ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 5, ADDITIONAL: 3 ;; QUESTION SECTION: ;heise.de. IN A ;; ANSWER SECTION: heise.de. 2266 IN A 18.104.22.168 ;; AUTHORITY SECTION: heise.de. 1622 IN NS ns.pop-hannover.de. heise.de. 1622 IN NS ns.s.plusline.de. heise.de. 1622 IN NS ns.plusline.de. heise.de. 1622 IN NS ns2.pop-hannover.net. heise.de. 1622 IN NS ns.heise.de. ;; ADDITIONAL SECTION: ns.plusline.de. 265 IN A 22.214.171.124 ns.pop-hannover.de. 5113 IN A 126.96.36.199 ns2.pop-hannover.net. 15150 IN A 188.8.131.52 ;; Query time: 2 msec ;; SERVER: 184.108.40.206#53(220.127.116.11) ;; WHEN: Tue Oct 9 13:03:50 2012 ;; MSG SIZE rcvd: 216