Lost DNS lookup

[McGuffey, David C.]

A few days ago, a workstation in a lab stopped doing DNS lookups to
support connectivity to SMTP, POP, and web services.  As I think back,
the behavior started in close proximity in time to a stunnel update.

Checked the usual locations and all seems to be ok.  /etc/resolv.conf,
/etc/nsswitch.conf, /etc/host and /etc/networks files look ok.  Running
ifconfig in a terminal shows that DHCP on the boundary firewall gave it
a good address, netmask, and gateway. The machine still serves up an
ext3 partition via samba to some windowze machines on the 192.168.1.0
network, and still prints to two network printers via cups (same
192.168.1.0 network), so it is not a hardware problem. The two other
windowze machines on the network can reach the web via Firefox, but the
fedora 7 box won't, so I don't believe it is a firewall problem (nothing
has changed there).

As a last resort, I executed the normal windowze solution...a reboot.
That did not solve the problem.

Lights on the local 8-port switch don't seem to indicate any network
traffic when an nslookup command is issued.  I don't believe it is
issuing DNS requests through the gateway to the dns server...but will
confirm with tshark later today/this evening.

Any ideas?

Dave McGuffey
Principal Information System Security Engineer // NSA-IEM, NSA-IAM
SAIC, IISBU, Columbia, MD