nslookup strangeness

[emck]

First let me describe my setup. I have 2 computers behind a router, one desktop and one portable. The desktop is setup with a static IP and the portable is setup with dhcp.

When I send the command nslookup www.apple.com on the desktop I get:
*** Can't find server name for address 192.168.123.254: Non-existent host/domain
*** Default servers are not available


When I issue the same command on the portable I get a different result:
Server: wbnms02.ne.ipsvc.net
Address: 24.128.0.26

Non-authoritative answer:
Name: www.apple.com.akadns.net
Address: 17.254.0.91
Aliases: www.apple.com


Do you know how I can fix this problem? Do you think it's related to another problem that I have - it takes forever when I try to connect to the desktop or check email or when I connect with ssh.

thanks

edward

 

[blb]

Originally posted by emck
...
When I send the command nslookup www.apple.com on the desktop I get:
*** Can't find server name for address 192.168.123.254: Non-existent host/domain
*** Default servers are not available

In this case, your desktop is using 192.168.123.254 as its DNS server, but the IP doesn't reverse (map back to a hostname).

When I issue the same command on the portable I get a different result:
Server: wbnms02.ne.ipsvc.net
Address: 24.128.0.26

Non-authoritative answer:
Name: www.apple.com.akadns.net
Address: 17.254.0.91
Aliases: www.apple.com

Is there a reason you use a different DNS server for the two machines? Using this DNS server for the desktop will most likely fix the desktop's problem.

Do you know how I can fix this problem? Do you think it's related to another problem that I have - it takes forever when I try to connect to the desktop or check email or when I connect with ssh.

thanks

edward

Usually delays like this indicate a common DNS problem of IP addresses not mapping back to hostnames; a number of services will try to resolve an IP back to a hostname, and if that IP isn't setup, will take some time, hence the delay.

 

[emck]

thanks so much it seem to all work out except that I am still having some slow ssh connection when I look at the logs it tell me that it can not reverse lookup and also some other information about lastlog.


sshd[424]: lastlog_openseek: /var/log/lastlog is not a file or directory!
Mar 14 08:15:07 BlueTuna sshd[424]: Could not reverse map address 192.168.123.177.
Mar 14 08:15:07 BlueTuna sshd[424]: lastlog_perform_login: Couldn't stat /var/log/lastlog: No such file or directory

It would be great if someone could point me in the right direction to fix the reverse lookup problem

Edward

 

[SCrossman]

IP addresses in the 192.168.x.x are only used for internal non-routeable IPs in a private network. This address could only be used, I think if you have a local DNS server. If this is entered in your DNS, in the network prefs pane, remove it.