Hi all,
I'm attempting to manage a google-compute system running debian/ubuntu;
I normally run a freebsd system so I'm out of my element here and web
searches haven't helped:
81~16.04.1-Ubuntu SMP Mon May 11 14:56:45 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux
When originally built, the system had a screwed-up postfix installation;
in attempting to solve this problem, I wanted to uninstall postfix and
reinstall it. However, I don't think I should do that because the postfix
installation has an issue:
$ aptitude why postfix
i automysqlbackup Depends bsd-mailx | mailx
i A bsd-mailx Depends default-mta | mail-transport-agent
i A postfix Provides mail-transport-agent
$ dpkg --simulate --remove postfix
dpkg: could not open log '/var/log/dpkg.log': Permission denied
dpkg: dependency problems prevent removal of postfix:
bsd-mailx depends on default-mta | mail-transport-agent; however:
Package default-mta is not installed.
Package postfix which provides default-mta is to be removed.
Package mail-transport-agent is not installed.
Package postfix which provides mail-transport-agent is to be removed.
bsd-mailx depends on default-mta | mail-transport-agent; however:
Package default-mta is not installed.
Package postfix which provides default-mta is to be removed.
Package mail-transport-agent is not installed.
Package postfix which provides mail-transport-agent is to be removed.
dpkg: error processing package postfix (--remove):
dependency problems - not removing
Processing triggers for libc-bin (2.23-0ubuntu10) ...
dpkg: cycle found while processing triggers:
chain of packages whose triggers are or may be responsible:
libc-bin -> libc-bin
packages' pending triggers which are or may be unresolvable:
libc-bin: ldconfig
dpkg: error processing package libc-bin (--remove):
triggers looping, abandoned
Errors were encountered while processing:
postfix
libc-bin
If I consider removing libc-bin so I can re-install it and correct the
dependency loop, I am unable to do so:
$ dpkg --simulate --remove libc-bin
dpkg: could not open log '/var/log/dpkg.log': Permission denied
dpkg: error processing package libc-bin (--remove):
this is an essential package; it should not be removed
Processing triggers for libc-bin (2.23-0ubuntu10) ...
dpkg: cycle found while processing triggers:
chain of packages whose triggers are or may be responsible:
libc-bin -> libc-bin
packages' pending triggers which are or may be unresolvable:
libc-bin: ldconfig
dpkg: error processing package libc-bin (--remove):
triggers looping, abandoned
Errors were encountered while processing:
libc-bin
libc-bin
I then considered forcing removal of postfix by ignoring dependencies, but
that has the same libc-bin loop issue:
$ dpkg --simulate --ignore-depends bsd-mailx --purge postfix
dpkg: could not open log '/var/log/dpkg.log': Permission denied
(Reading database ... 171222 files and directories currently installed.)
Would remove or purge postfix (3.1.0-3ubuntu0.3) ...
Processing triggers for libc-bin (2.23-0ubuntu10) ...
dpkg: cycle found while processing triggers:
chain of packages whose triggers are or may be responsible:
libc-bin -> libc-bin
packages' pending triggers which are or may be unresolvable:
libc-bin: ldconfig
dpkg: error processing package libc-bin (--purge):
triggers looping, abandoned
Errors were encountered while processing:
libc-bin
Can anyone give me some clues on how to resolve this?
The main goal is to uninstall postfix and re-install it, without uninstalling
the automysqlbackup as this is a production system and the autobackup is
working properly. I believe the postfix dependency is for cases where the
auto-backup fails; it's also preventing mail from being delivered for failing
cron jobs.
Sorry for the naivete of this; I'm new to linux.
Lots of the apt and dpkg functions require Root or Sudo. Notice the "Permission denied" phases mixed in with the responses.
Good luck,
Kenneth Parker