Unmet dependencies. How to downgrade a package?

[dazz100]

Hello

I am trying to install dchp3 server but I have hit a problem with unmet dependancies. It appears that I have a later version isc-dhcp-common than Unbuntu 12.04 expects. I don't know how to downgrade to the earlier version to fix this problem.

apt-get doesn't seem to be able to cope with this problem.



dazz@toshiba:~$ sudo apt-get -f install
Reading package lists... Done
Building dependency tree
Reading state information... Done
Correcting dependencies... Done
The following packages were automatically installed and are no longer required:
linux-headers-3.2.0-26-generic linux-headers-3.2.0-26 linux-headers-3.2.0-26-generic-pae
Use 'apt-get autoremove' to remove them.
The following extra packages will be installed:
isc-dhcp-server
Suggested packages:
isc-dhcp-server-ldap
The following packages will be upgraded:
isc-dhcp-server
1 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
1 not fully installed or removed.
Need to get 0 B/427 kB of archives.
After this operation, 0 B of additional disk space will be used.
Do you want to continue [Y/n]? y
dpkg: dependency problems prevent configuration of isc-dhcp-server:
isc-dhcp-server depends on isc-dhcp-common (= 4.1.ESV-R4-0ubuntu5.2); however:
Version of isc-dhcp-common on system is 4.1.ESV-R4-0ubuntu5.5.
dpkg: error processing isc-dhcp-server (--configure):
dependency problems - leaving unconfigured
No apport report written because the error message indicates its a followup error from a previous failure.
Errors were encountered while processing:
isc-dhcp-server
E: Sub-process /usr/bin/dpkg returned an error code (1)

[bart.a]

Have you tried removing the package and reïnstalling the "older" package?
Note that I do not know what removing/downgrading the package will do to your current configuration.

First, check available versions you can install:

apt-cache showpkg packagename

Install the version you need:

sudo apt-get install packagename=version

Prevent auto updating the package to the newer version. Remind yourself that you are holding this version. You will be able to upgrade it eventualy:

sudo echo “package hold” | sudo dpkg –set-selections

[dazz100]

Hi

Unfortunately non of those commands worked. Nothing I do seems to budge the wrong version. apt-get doesn't seem to be able to fix this problem.

I have tried commands on isc-dhcp-server and dhcp3-server but no progress.

Still stuck.

Regards


Dazz

[dazz100]

Hi

I think the answer is here:
http://forums.hak5.org/index.php?/topic/26455-dhcp3-server/
using Synaptic to force the lower version.
I then uninstalled dhcp3-server and reinstalled.

I got different error messages that I think just say dhcp3 needs to be configured. I need to do some further testing.

Dazz

[bart.a]

using synaptic is the graphical way of going about things.. basically it's doing the same..

You have removed the old and installed a new version, so it needing configuration is possible..

[dazz100]

Hi
The difference between synaptic and apt-get is that synaptic solved this problem and apt-get didn't.

I am now trying to configure isc-dhcp-server. The unmet dependancies problem has gone.

Dazz

[bart.a]

you're right! it did.. that is a big difference :lolflag: