ubuntu server 12.04 can not remove dhcp-client

ubuntu linux-networking

19,229

Solution 1

I never had Ubuntu behave like this, so this is just a wild guess: It could have something to do with 'network-manager'.

As to the removal of dhcp-client:

You are trying to remove a virtual package. Virtual packages don't really exist they are just provided by some packages to declare they provide a similar service/function (see also Debian Policy Manual). IIRC the default dhcp-client package installed by ubuntu is 'isc-dhcp-client', but no mater which one is installed on your system you probably will have a rather hard time removing it cleanly as quite some other packages depend on it being installed.

Solution 2

You probably didn't take the interface down before reconfiguring it, and so there is still a DHCP client running in the background trying to maintain the DHCP IP. Check for this with ps -eF | grep dhclient and kill the process.

If you really want to uninstall the DHCP client (which you shouldn't need to), you need to remove the dhcp3-client package.

Solution 3

You need to remove the isc-dhcp-client completely. If DNS-server addresses are configured both in the isc-dhcp-client and in /etc/network/interfaces file the addresses in the client configuration always take precedence and will be the ones that are written to /etc/resolv.conf. If you want the dns-servers setting in /etc/network/interfaces to be written to /etc/resolv.conf you will have to remove the isc-dhcp-client completely.

The apt-get --purge remove isc-dhcp-client isc-dhcp-common command will do just that. If that does not do the trick find and remove these two files:

/run/resolvconf/interface/eth0.dhclient and /run/resolvconf/interface/original.resolvconf

19,229

rgc

Updated on September 18, 2022

Comments

rgc almost 2 years
When I change network from dhcp to static, it will periodically change IP to the dhcp configuration and ignore the configuration of /etc/network/interface.

So I want to remove the dhcp-client, however when I remove it in Ubuntu, I encounter this problem. Can you give me some help ?
```
$ sudo apt-get remove dhcp-client
Reading package lists... Done
Building dependency tree
Reading state information... Done
**Virtual packages like 'dhcp-client' can't be removed**
0 upgraded, 0 newly installed, 0 to remove and 77 not upgraded.
```
this is my interface file content:
```
auto eth0
#iface eth0 inet dhcp
iface eth0 inet static
address 10.0.0.7
netmask 255.255.255.0
gateway 10.0.0.1
# This is an autoconfigured IPv6 interface
iface eth0 inet6 auto
```
- Chida almost 12 years
  
  Can you post your /etc/network/interfaces file?
- rgc almost 12 years
  
  i have post my interface file
- Chida almost 12 years
  
  See my answer below to update the interfaces file
- Kcmamu over 11 years
  
  I've seen this on a bunch of systems I was in the process of setting up recently after manually editing /etc/network/interfaces and restarting networking, I kept seeing hosts disappear. As I hadn't commissioned the systems, I was able to reboot them, which solved the problem.
rgc almost 12 years

i am sorry, i have lost #, it was commented in interface file. when copy from file, i lost it.
hpcodeit over 11 years

This is ineffective in 12.04 or 12.10. As mgorven pointed out, dhclient is still running in the background.