I can ping the google.com ip addresses (209.85.231.104) but can't ping the FQDN, obviously DNS is broken. I can also ping the nameserver ip addresses specified in /etc/resolv.conf. -- Gaurav On Sun, Mar 7, 2010 at 10:48 PM, Gaurav Nangla <gaurav.knangla at gmail.com>wrote:> Hi Everyone, >I've setup a Centos 5.4 (x86_64) box in a VM recently; the trouble is I just> can't get internet to work on it. > > Pinging the resolved google.com ips, nameserver ips works fine but DNS > lookup queries don't. > > Here's some of the digging around that I did: > > dig google.com > ; <<>> DiG 9.3.6-P1-RedHat-9.3.6-4.P1.el5 <<>> google.com > ;; global options: printcmd > ;; connection timed out; no servers could be reached > > nslookup google.com > ;; connection timed out; no servers could be reached > > I didn't observe any UDP/TCP packets during dig and nslookup either > > cat /etc/resolv.conf > ; generated by /sbin/dhclient-script > > nameserver 208.67.220.220 > > nameserver 208.67.222.222 > > Also my /etc/nsswitch.conf is in order and contains the "hosts: files dns" > entry. > > What could be wrong? > > -- > Best Regards, > Gaurav >-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.centos.org/pipermail/centos/attachments/20100308/298abbbd/attachment-0002.html>
Greetings, On Mon, Mar 8, 2010 at 11:04 AM, Gaurav Nangla <gaurav.knangla at gmail.com> wrote:> I can ping the google.com ip addresses (209.85.231.104) but can't ping the > FQDN, obviously DNS is broken. > > I can also ping the nameserver ip addresses specified in /etc/resolv.conf. >Just a thought: why don't you try google nameserver 8.8.8.8 in resolv.conf as the only server. Regards, Rajagopal
Gaurav Nangla wrote:> I can ping the google.com <http://google.com> ip addresses > (209.85.231.104) but can't ping the FQDN, obviously DNS is broken. > > I can also ping the nameserver ip addresses specified in /etc/resolv.conf.well, the DNS servers given by your resolv.conf output seem valid from here.. I recommend doing some more debugging with `host` or similar DNS diagnostic tools. note regular DNS lookups like these tend to use UDP rather than TCP, if you're behind a NAT firewall which doesn't allow outbound udp port 53 and connection track the response, then things might not work well. $ host google.com 208.67.220.220 Using domain server: Name: 208.67.220.220 Address: 208.67.220.220#53 Aliases: google.com has address 74.125.19.105 google.com has address 74.125.19.99 google.com has address 74.125.19.103 google.com has address 74.125.19.106 google.com has address 74.125.19.147 google.com has address 74.125.19.104 google.com mail is handled by 400 google.com.s9b2.psmtp.com. google.com mail is handled by 200 google.com.s9a2.psmtp.com. google.com mail is handled by 300 google.com.s9b1.psmtp.com. google.com mail is handled by 100 google.com.s9a1.psmtp.com. $ host google.com 208.67.222.222 Using domain server: Name: 208.67.222.222 Address: 208.67.222.222#53 Aliases: google.com has address 74.125.19.105 google.com has address 74.125.19.147 google.com has address 74.125.19.99 google.com has address 74.125.19.103 google.com has address 74.125.19.104 google.com has address 74.125.19.106 google.com mail is handled by 400 google.com.s9b2.psmtp.com. google.com mail is handled by 200 google.com.s9a2.psmtp.com. google.com mail is handled by 300 google.com.s9b1.psmtp.com. google.com mail is handled by 100 google.com.s9a1.psmtp.com.
UPDATE: I tried with FreeBSD8 as well and the DNS query didn't work. This is beginning to look more and more like an issue with my UTStarcom *WA3002G4 ADSL2+ Router and its NAT config or the lack of it.* * * *My setup and the ip addresses:* *Router 192.168.1.1* *Windows 192.168.1.2* *Centos 5.4 192.168.1.3* *FreeBSD8 192.168.1.4* * * *The windows host works fine with no issues with DNS queries.* Best Regards, Gaurav On Tue, Mar 9, 2010 at 12:08 AM, Gaurav Nangla <gaurav.knangla at gmail.com>wrote:> [root at cent5 ~]# dig www.google.com @208.67.220.220 > > ; <<>> DiG 9.3.6-P1-RedHat-9.3.6-4.P1.el5 <<>> www.google.com @ > 208.67.220.220 > ;; global options: printcmd > ;; connection timed out; no servers could be reached > > Best Regards, > Gaurav > > > > On Mon, Mar 8, 2010 at 5:21 PM, Pitshou Asingalembi <depitsho at yahoo.fr>wrote: > >> John R Pierce wrote: >> > Gaurav Nangla wrote: >> > >> >> I can ping the google.com <http://google.com> ip addresses >> >> (209.85.231.104) but can't ping the FQDN, obviously DNS is broken. >> >> >> >> I can also ping the nameserver ip addresses specified in >> /etc/resolv.conf. >> >> >> > >> > well, the DNS servers given by your resolv.conf output seem valid from >> > here.. I recommend doing some more debugging with `host` or similar DNS >> > diagnostic tools. >> > >> > note regular DNS lookups like these tend to use UDP rather than TCP, if >> > you're behind a NAT firewall which doesn't allow outbound udp port 53 >> > and connection track the response, then things might not work well. >> > >> > >> > $ host google.com 208.67.220.220 >> > Using domain server: >> > Name: 208.67.220.220 >> > Address: 208.67.220.220#53 >> > Aliases: >> > >> > google.com has address 74.125.19.105 >> > google.com has address 74.125.19.99 >> > google.com has address 74.125.19.103 >> > google.com has address 74.125.19.106 >> > google.com has address 74.125.19.147 >> > google.com has address 74.125.19.104 >> > google.com mail is handled by 400 google.com.s9b2.psmtp.com. >> > google.com mail is handled by 200 google.com.s9a2.psmtp.com. >> > google.com mail is handled by 300 google.com.s9b1.psmtp.com. >> > google.com mail is handled by 100 google.com.s9a1.psmtp.com. >> > >> > $ host google.com 208.67.222.222 >> > Using domain server: >> > Name: 208.67.222.222 >> > Address: 208.67.222.222#53 >> > Aliases: >> > >> > google.com has address 74.125.19.105 >> > google.com has address 74.125.19.147 >> > google.com has address 74.125.19.99 >> > google.com has address 74.125.19.103 >> > google.com has address 74.125.19.104 >> > google.com has address 74.125.19.106 >> > google.com mail is handled by 400 google.com.s9b2.psmtp.com. >> > google.com mail is handled by 200 google.com.s9a2.psmtp.com. >> > google.com mail is handled by 300 google.com.s9b1.psmtp.com. >> > google.com mail is handled by 100 google.com.s9a1.psmtp.com. >> > _______________________________________________ >> > CentOS mailing list >> > CentOS at centos.org >> > http://lists.centos.org/mailman/listinfo/centos >> > >> > >> please try: >> dig www.google.com @IPofyourDNSserver >> and send me the output >> _______________________________________________ >> CentOS mailing list >> CentOS at centos.org >> http://lists.centos.org/mailman/listinfo/centos >> > >-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.centos.org/pipermail/centos/attachments/20100309/51337c46/attachment-0002.html>
On Tue, 2010-03-09 at 01:25 +0530, Gaurav N. wrote:> UPDATE: > > > I tried with FreeBSD8 as well and the DNS query didn't work. This is > beginning to look more and more like an issue with > my UTStarcom WA3002G4 ADSL2+ Router and its NAT config or the lack of > it. > > > My setup and the ip addresses: > Router 192.168.1.1 > Windows 192.168.1.2 > Centos 5.4 192.168.1.3 > FreeBSD8 192.168.1.4 > > > The windows host works fine with no issues with DNS queries.--- Hey do this for me since nothing seems to work. Log into your DSL Modem/Router and get your DNS server IP Addresses and put them into: resolve.conf nameserver x.x.x.x nameserver x.x.x.x I have had certain router/modems that i have installed and have had to do this because dhcp would not get the nameservers. John