DNS not resolving host names on server

[cdlvj]

SCO OpenServer 5.05 which has been running fine for a bunch of years.

Something has messed up or dns. When I do a nslookup for any outside servers, I get Can't find

http://www.domain.com:

Non-existent Host/Domain.

One of the culprits may have been a router firmware upgrade.
ns1/ns2 act as our secondary. nslookup from home computer resolve all my domains.

Are there any ports that need to be opened?
Thanks in advance.

 

[Annihilannic]

What are you using as a DNS server (check contents of /etc/resolv.conf? Often the router itself acts as a DNS server, forwarding requests to your ISP's DNS, which should mean that no opening of ports is required.



Annihilannic.

 

[cdlvj]

I have

nameserver 0.0.0.0
hostresorder bind local

why does dig work and return info.
nslookup.

0.0.0.0 defaults to the system bind.
if I put the server ext ip/int ip then nslookup just hangs and has to be breaked.

 

[Annihilannic]

Does your SCO server use a fixed IP or does it obtain its IP address via DHCP? If it uses DHCP, presumably the router is the one that supplies the IP address and DNS configuration, in which case you may have to renew the DHCP lease. Unfortunately I don't have a SCO system any more to check how to do this... or whether it's even possible under SCO.

Annihilannic.

 

[cdlvj]

No, have a static address, and the machine is in the dmz.

DHCP is disabled.

 

[Annihilannic]

What happens if you try to use the router as a DNS server (some routers forward DNS requests to your ISP DNS server) , e.g. nslookup

http://www.domain.com

IP_address_of_router?

Annihilannic.

 

[cdlvj]

# nslookup

http://www.ktsa.com

192.168.0.1
*** Can't find server name for address 192.168.0.1: Non-existent host/domain
*** Default servers are not available

# ping 192.168.0.1
PING 192.168.0.1 (192.168.0.1): 56 data bytes
64 bytes from 192.168.0.1: icmp_seq=0 ttl=150 time=0 ms
64 bytes from 192.168.0.1: icmp_seq=1 ttl=150 time=0 ms
64 bytes from 192.168.0.1: icmp_seq=2 ttl=150 time=0 ms

--- 192.168.0.1 ping statistics ---
3 packets transmitted, 3 packets received, 0% packet loss
round-trip min/avg/max = 0/0/0 ms
#

 

[Annihilannic]

Hmm... so much for that idea.

What did you mean by "ns1/ns2 act as our secondary"? Are they DNS servers? If you do an nslookup against them, does that work?

Annihilannic.

 

[cdlvj]

ns1.swbell.net and ns2.swbell.net (acting as secondary)

nslookup
server ns1.swbell.net

returns some, my main machine
but errors on

http://www.tek-tips.com,

aspn.activestate.com

 

[cdlvj]

We have noticed that the dns server is not being resolved, and shows the address 0.0.0.0

Server: ns.dnserver.com
Address: 0.0.0.0
ns.dnserver.com can't find ftp.domain.com. Non-existent host/domain.

 

[kangaroojack]

This a sample of /etc/resolv.conf

hostresorder local bind
nameserver 192.168.1.1
domain mydomain.au
search customers.mydomain.au intranet.mydomain.au

We are using a 'win' server like DNS server.
And our SCO box uses it to resolve names in different zones.
Hope this will helps you