Bug 1454719

Description of problem:

When testing upgrade from RHEL 7.3 ipa-server image (version 4.4.0-41 from official registry) to a development version of RHEL 7.4 image, the upgrade code fails due to attempting to unconfigure ipa_memcache service which is not present in FreeIPA 4.5.x:

```console
Upgrading IPA:. Estimated time: 1 minute 30 seconds
  [1/8]: saving configuration
  [2/8]: disabling listeners
  [3/8]: enabling DS global lock
  [4/8]: starting directory server
  [5/8]: updating schema
  [6/8]: upgrading server
  [7/8]: stopping directory server
  [8/8]: restoring configuration
Done.
Update complete
Upgrading the configuration of the IPA services
[Verifying that root certificate is published]
[Migrate CRL publish directory]
Publish directory already set to new location
Upgraded /etc/httpd/conf.d/ipa.conf to version 26
Upgraded /etc/httpd/conf.d/ipa-pki-proxy.conf to version 10
/etc/dirsrv/slapd-EXAMPLE-TEST/certmap.conf is now managed by IPA. It will be overwritten. A backup of the original will be made.
Upgraded /etc/dirsrv/slapd-EXAMPLE-TEST/certmap.conf to version 3
[Verifying that CA proxy configuration is correct]
[Verifying that KDC configuration is using ipa-kdb backend]
Upgrading IPA services
Unconfiguring ipa_memcached
IPA server upgrade failed: Inspect /var/log/ipaupgrade.log and run command ipa-server-upgrade manually.
Unexpected error - see /var/log/ipaupgrade.log for details:
CalledProcessError: Command '/bin/systemctl stop ipa_memcached.service' returned non-zero exit status 5
```

ipaupgrade.log shows:

```console
Starting external process
2017-05-23T08:05:01Z DEBUG args=/bin/systemctl stop ipa_memcached.service
2017-05-23T08:05:02Z DEBUG Process finished, return code=5
2017-05-23T08:05:02Z DEBUG stdout=
2017-05-23T08:05:02Z DEBUG stderr=Failed to stop ipa_memcached.service: Unit ipa_memcached.service not loaded.

2017-05-23T08:05:02Z ERROR IPA server upgrade failed: Inspect /var/log/ipaupgrade.log and run command ipa-server-upgrade manually.
2017-05-23T08:05:02Z DEBUG   File "/usr/lib/python2.7/site-packages/ipapython/admintool.py", line 172, in execute
    return_value = self.run()
  File "/usr/lib/python2.7/site-packages/ipaserver/install/ipa_server_upgrade.py", line 46, in run
    server.upgrade()
  File "/usr/lib/python2.7/site-packages/ipaserver/install/server/upgrade.py", line 1905, in upgrade
    upgrade_configuration()
  File "/usr/lib/python2.7/site-packages/ipaserver/install/server/upgrade.py", line 1655, in upgrade_configuration
    uninstall_ipa_memcached()
  File "/usr/lib/python2.7/site-packages/ipaserver/install/server/upgrade.py", line 87, in uninstall_ipa_memcached
    ipa_memcached.uninstall()
  File "/usr/lib/python2.7/site-packages/ipaserver/install/service.py", line 681, in uninstall
    self.stop()
  File "/usr/lib/python2.7/site-packages/ipaserver/install/service.py", line 398, in stop
    self.service.stop(instance_name, capture_output=capture_output)
  File "/usr/lib/python2.7/site-packages/ipaplatform/base/services.py", line 283, in stop
    ipautil.run(args, skip_output=not capture_output)
  File "/usr/lib/python2.7/site-packages/ipapython/ipautil.py", line 495, in run
    raise CalledProcessError(p.returncode, arg_string, str(output))
```

The root cause of this error is in the fact that the new image bind-mounts the old image data volume whose var/lib/ipa/sysrestore/sysrestore.state holds configuration status for ipa_memcached.

This leads the upgrader to attempt to unconfigure the service, however there is no ipa_memcached unit file present anymore, so an attempt to stop it inevitably fails. Additionally, even if the state file lists the service as not running and not enabled, the uninstaller still attempts to unconditionally stop and disable the service.

We should either honor the settings in the state file or make it possible to recover gracefully from the mismatch between the reported state and actual state in the environment.

Version-Release number of selected component (if applicable):
ipa-version in the RHEL 7.4 image: ipa-server-common.noarch 0:4.5.0-13.el7 

How reproducible:

Always

Steps to Reproduce:
1. install ipa-server container from registry.access.redhat.com/rhel7/ipa-server:latest
2. upgrade to a devel version of ipa-server RHEL 7.4 image

Actual results:

Upgrade fails on failed attempt to stop ipa_memcached

Expected results:

Upgrade is successful and the new container can continue to work with old data