Signed-off-by: Michael Hanselmann <hansmi@google.com>
Reviewed-by: Iustin Pop <iustin@google.com>

This patch brings a huge change to ganeti-watcher to make it aware of
node groups. Each node group is processed in its own subprocess,
reducing the impact of long-running operations.

The global watcher state file, $datadir/ganeti/watcher.data, is replaced
with a state file per node group ($datadir/ganeti/watcher.${uuid}.data).

Previously a lock on the state file was used to ensure only one instance
of watcher was running at the same time. Some operations, e.g.
“gnt-cluster renew-crypto”, blocked the watcher by acquiring an
exclusive lock on the state file. Since the watcher processes now use
different files, this method is no longer usable. Locking multiple files
isn't atomic. Instead a dedicated lock file is used and every watcher
process acquires a shared lock on it. If a Ganeti command wants to block
the watcher it acquires the lock in exclusive mode.

Each per-nodegroup watcher process also acquires an exclusive lock on
its state file. This prevents multiple watchers from running for the
same nodegroup.

The code is reorganized heavily to clear up dependencies between
functions and to get rid of the global “client” variable. The utility
class “Watcher” is removed in favour of stand-alone utility functions.

Since the parent watcher process won't wait for its children by
default, a new option (--wait-children) was added. It is used, for
example, by QA.

Signed-off-by: Michael Hanselmann <hansmi@google.com>
Reviewed-by: Iustin Pop <iustin@google.com>

WATCHER_STATEFILE will be removed at the end of this
patch series.

Signed-off-by: Michael Hanselmann <hansmi@google.com>
Reviewed-by: Iustin Pop <iustin@google.com>

Instead of hardcoded Xen commands. This will make it work for all
hypervisors, instead of duplicating hypervisor functionality in QA
itself.

The timeout has been removed as gnt-instance stop itself will make
sure the instance is down before returning. We just double-check that
it is indeed down.

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: René Nussbaumer <rn@google.com>

Currently, 95% of the QA commands are executed in the same way: on the
master, based on a command list and with expectancies for succes:

    AssertEqual(StartSSH(master['primary'],
                         utils.ShellQuoteArgs(cmd)).wait(), 0)

The rest 5% are variations on this theme (maybe the command needs to
fail, or the node is different, etc.). Based on this, we can simplify
the code significantly if we abstract the common theme into a new
AssertCommand() function. This saves ~250 lines of code in the QA suite,
around 8% of the entire QA code size.

Additionally, the output was very cryptic before (the famous "QA error:
1 != 0" messages), whereas now we show a clear error message (node,
command, exit code and failure mode).

The patch replaces single quotes with double quotes in all the parts of
the code that I touch; let me know if that's not OK…

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Michael Hanselmann <hansmi@google.com>

… instead of an object. Allows it to be used in places where
only the name is available.

Signed-off-by: Michael Hanselmann <hansmi@google.com>
Reviewed-by: René Nussbaumer <rn@google.com>

The interaction with cron-launched watcher is a well-known failure mode of QA:

---- 2010-10-14 06:54:55.464839 time=0:00:56.764827 Test tools/move-instance

For the following tests it's recommended to turn off the ganeti-watcher cronjob.

---- 2010-10-14 06:54:55.465255 start Test automatic restart of instance by ganeti-watcher
…
Error: Domain 'instance1' does not exist.
Command: ssh -oEscapeChar=none -oBatchMode=yes -l root -t -oStrictHostKeyChecking=yes
  -oClearAllForwardings=yes -oForwardAgent=yes node2 'ganeti-watcher -d'
2010-10-13 23:55:04,479:  pid=1659 ganeti-watcher:626
 ERROR Can't acquire lock on state file /var/lib/ganeti/watcher.data: File already locked
---- 2010-10-14 06:55:04.513948 time=0:00:09.048693 Test automatic restart of instance by ganeti-watcher

In order to fix this, we disable the watcher during these tests, and
re-enable it afterwards. To protect against watcher being disabled, we
enable it unconditionally at the start of the QA (we do want it enabled,
in order to see the interaction between the watcher and many
creation/disk replace jobs, etc.).

Note: even after this patch, if a cron-watcher was started and is still
running during the test, we'll have locking issues. I think for now this
is OK, we'll have to see how often that happens.

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Michael Hanselmann <hansmi@google.com>

To my knowledge they're used nowhere and it's at least slightly
confusing to people adding new QA checks.

Reviewed-by: ultrotter

Reviewed-by: iustinp

- When line wrapping is needed, move spaces to the next line.
- Remove embedded line breaks from error messages.

Reviewed-by: schreiberal

Reviewed-by: schreiberal

This makes the tests much more reliably because it avoids race conditions.
It also helps to speed them up a lot.

Reviewed-by: iustinp

Make the code somewhat smaller. Disable disk failure test for master for now.

Reviewed-by: schreiberal

- Implement colours in qa_utils.
- Print warning for cron script.

Reviewed-by: iustinp

- Test “gnt-backup export” and “gnt-backup import”.
- Move “ResolveInstanceName” to qa_utils.py.
- Fix tests for “ganeti-watcher”.
- Make instance shutdown and startup configurable.

Reviewed-by: schreiberal

Reviewed-by: iustinp