I created the local mirror to upgrade all lucid workstations in my network to precise. The problem is that the upgrade tool (link below) - precise.tar.gz always download packages from archive.ubuntu.com (19% [Waiting for headers] [Connecting to archive.ubuntu.com (126.96.36.199)]). I edited the precise.tar.gz file by modifying some files of it, putting it to my local mirror, modified the meta-release URL to my local mirror. Running do-release-upgrade I have the error below. My question is how to sign the precise.tar.gz package myself?
Checking for a new ubuntu release
Done Upgrade tool signature
Done Upgrade tool
authenticate 'precise.tar.gz' against 'precise.tar.gz.gpg'
exception from gpg: GnuPG exited non-zero, with code 1
gpg: Signature made Mon 04 Jun 2012 08:40:31 PM ICT using DSA key ID 437D05B5
gpg: /tmp/tmpMaz62f/trustdb.gpg: trustdb created
gpg: BAD signature from "Ubuntu Archive Automatic Signing Key "
Authenticating the upgrade failed. There may be a problem with the network or with the server.
Name: Precise Pangolin
Version: 12.04 LTS
Date: Thu, 26 Apr 2012 12:04:00 UTC
Description: This is the 12.04 LTS release