[SOLVED] unable to resolve host

[MacDuff]

Have been trying to get a USRobotics USB modem to work with my Ubuntu machine without success but after trying several things, I find that I have now broken my wireless network and appear to have lost root privileges.

When I try to do anything in a terminal using the sudo command, the following message appears:
sudo: unable to resolve host T-61
sudo: /etc/sudoers is mode 0460, should be 0440

How can I fix this please and thank you.

[sisco311]

reboot in recovery mode and in the root shell type:

chmod 0440 /etc/sudoers

open the /etc/hosts file for editing:
nano /etc/hosts
and edit it to look like this:
127.0.0.1 localhost
127.0.1.1 T-61

# The following lines are desirable for IPv6 capable hosts
::1 ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
ff02::3 ip6-allhosts
(change T-61.?XYZ? in the second line to T-61)

save the file and exit(Ctrl+o, Enter, Ctrl+x)

type:
exitand select the resume normal boot option.

[MacDuff]

sisco311, your suggestion makes sense and I will give it a try as soon as I have finished backing up the Home directory on that computer. I may have broken it so badly by trying out a bunch of edits to make the USB modem work that it may be better to rebuild the system.

I have a follow-up question if you don't mind. Forgive me for being so thick. You suggest changing the computer name to "T". I understand that "/etc/hosts" and /etc/hostname must have the same name. That has always been "T-61" but several times in the past few weeks as I have been struggling with networking, I have found that something in the system has changed the name in "hosts" by adding ".DHLTD" as a suffix. DHLTD is local workgroup (domain?). When that happens things seem to go in the ditch. I have been able to fix things by editing the offending file as root. This is the first time I have had a problem with the mode setting.

Does your suggestion to change the name to "T" suggest that I should not have the "-" in the name or were you making an assumption that "-61" was the error?

Any advice would be appreciated very much by this old man.

[sisco311]

sisco311, your suggestion makes sense and I will give it a try as soon as I have finished backing up the Home directory on that computer. I may have broken it so badly by trying out a bunch of edits to make the USB modem work that it may be better to rebuild the system.

I have a follow-up question if you don't mind. Forgive me for being so thick. You suggest changing the computer name to "T". I understand that "/etc/hosts" and /etc/hostname must have the same name. That has always been "T-61" but several times in the past few weeks as I have been struggling with networking, I have found that something in the system has changed the name in "hosts" by adding ".DHLTD" as a suffix. DHLTD is local workgroup (domain?). When that happens things seem to go in the ditch. I have been able to fix things by editing the offending file as root. This is the first time I have had a problem with the mode setting.

Does your suggestion to change the name to "T" suggest that I should not have the "-" in the name or were you making an assumption that "-61" was the error?

Any advice would be appreciated very much by this old man.
Sorry, my bad.
You should change T-61.whateverIsHere to T-61 .

[MacDuff]

Thank you sisco311

That fixed the problem of not being able to obtain root privileges.

Now I just have to sort out why I cannot get a network connection anymore. Perhaps I won't have to rebuild the system after all.

I appreciate your help very much.