How to change the IP Address on SCO Unix

One of my customers re-addressed their entire internal network to a new ip-address range to allow for future growth and DHCP server redundancy. They have a legacy Unix machine sitting in the corner that no one knows anything about, but they still need to access it for legacy data. I’m not a Unix guy so there may be easier ways to do this, but here’s how I changed the ip-address:

Login using the root account.
Run “ifconfig -a” to determine the interface name (which is net0 in the example below):

You can add an alias using “ifconfig net0 netmask broadcast”, but the alias will be removed when the system is rebooted.

To permanently change the ip-address, run “netconfig”.
Tab once and press the down arrow until “SCO TCP/IP” under the actual ethernet card is selected (not the one under the loopback adapter):

Tab back to the top and select “Modify protocol configuration” under “Protocol”:

Tab to the fields and make the necessary modifications. Tab to Ok and press enter:

Select OK:

Under the “Hardware” menu, select exit:

Select “Yes” to re-link the kernel:

Wait for the rebuilt to complete and choose yes:

I chose no on this one:

Modify the ip-addresses in /etc/hosts using the vi editor
vi hosts
i = insert mode
:q! to quit without saving
:wq to quit and save changes

Reboot and then run “ifconfig -a” to verify the settings are correct.



  1. Auto Insurance Directory

    Thank you for this post, really interesting. Feel free to comment on my blog, I was solving similar problem.

    • navi

      Hi my friend, i have working now on a enterprise who use SOC OPENSERVER RELEASE 5 and i dont have more connection to the server for datas.. we working on local red, but tre switch is desconfigurate for “who knows reason” how can i make connection directly again with the server from computers? i see the ip address but still connect with server :/ i hope your help

  2. Devi

    Thanks sir your blog was really healpful to me ..

  3. Grevy

    Please Mike help me ..
    Im triyng run netconfig , but , i see this message:

    cannot execute Permission Denied

  4. Syed Hasan

    Mike, It is great post. Thanks for your information along with screen shot. This post has solved my problem.


  5. Setareh

    Thank you so much for this helpful post.

  6. raselparvej

    Thanks for your share knowledge about SCO,

  7. fometeo

    Thank you, still useful at 2018, for a legacy SCO 5 🙂

  8. Ildefonso Giron

    Good help is timeless. Thanks a lot!


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