Do you mean that you have "more" than "one" network card, and that Slackware only shows you "one" of "two" network cards on your pc?

I run into this on all of my pc's using linux.

If so,

As root:

"ifconfig"

That shows what network cards are up and running at the time.

It should have a "lo" device you need that one.

It should show an "eth0", but it may have "eth1" instead.

If you have an "eth0" then as root "ifconfig eth1 up"

or if you have an "eth1" then try "ifconfig eth0 up"

then assuming that your 'router' or 'gateway/dns' is set up to assign ip addresses, as root: "dhcpcd eth0" or "dhcpdc eth1" depending on which interface you just brough online.

also there is 'ethtool' as well in linux . check 'man ethtool' as well.

Remember the "netconfig" tool is part of "pkgtool". The netconfig tool let's you do your network settings in slackware,but it only works for the eth0 device. The settings for netconfig go to: /etc/rc.d/rc.inet1.conf, /etc/resolv.conf

check those files and see what they say.

you may have to just manually move the settings for eth0 to eth1.

Also, slackware 11 is different know than all other slack versions as it uses udev.

Udev will on the fly for whatever reason, change a network card from running as 'eth0' to 'eth1' even when your using the pc. So you need to create a 'udev' rule.

Pat V of Slackware has more info on this in the "tips and help" readme file that's in the root directory of the slackware 11.0 install cd 1.

Remember making changes to udev should always be confirmed by rebooting the pc and seeing if your changes are actually hard coded.

As always make a backup of your config's before doing anything.

Actually, Slackware creates the udev rules for you. If you have multiple network cards, and they keep swapping names, check out /etc/udev/rules.d/network-devices.rules and remove the comment characters (#) from the lines that tie the interface names (eth0, eth1) to your network interfaces. Mine for instance has:
Eric