Currently, masterd startup with old software versions is very confusing
for users: we present two tracebacks, with a message in the middle about
"version mismatch". This can lead to users believing that all that needs
to be done is to fix the config file.

This patch attempts to improve this by handling this case in masterd
itself (not in the child), and showing a more friendly message for this
case.

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

This makes almost all of the daemons show error messages, and not return
until they finished listening on the appropriate sockets.

Masterd is the only one "special", as it doesn't do enough
initialization in the server creation, only later.

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

Currently, GenericMain does a two-staged workflow:

- Check, before forking
- then Exec, after forking

This means we don't have any possibility to treat preparation work
(before the daemon is ready for work) different from the actual work.

The patch adds another PreExec function that is run just before Exec,
and which should ensure that the daemon is ready for serving client
before it returns. Its result is then sent as the third argument to
Exec.

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

As already noted in the design document, an opcode's priority is
increased when the lock(s) can't be acquired within a certain amount of
time, except at the highest priority, where in such a case a blocking
acquire is used.

A unittest is provided. Priorities are not yet used for acquiring the
lock(s)—this will need further changes on mcpu.

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

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

This patch adds an initial implementation of a lock monitor, accessible
for the user through “gnt-debug locks”. It currently shows all resource
locks: BGL, nodes and instances. Config and job queue locks could be
shown too, but wouldn't be of much help.  The current owner(s) and mode
are also shown.

Showing pending acquires will require further changes on the SharedLock
internals and is not yet implemented.

Example output:
$ gnt-debug locks -o name,mode,owner
Name            Mode      Owner
BGL/BGL         shared    JobQueue19/Job147
instances/inst1 exclusive JobQueue19/Job147
instances/inst2 -         -
instances/inst3 -         -
instances/inst4 -         -
nodes/node1     exclusive JobQueue19/Job147
nodes/node2     exclusive JobQueue19/Job147

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

This patch enables IPv6 name resolution by using socket.getaddrinfo
instead of socket.gethostbyname_ex.

It renames the HostInfo class to Hostname and unifies its use throughout
the code. This is achieved by using static calls where no object is
needed and removes some obsolete code.

For now, we just resolve to IPv4 addresses, but this will change once it
is needed.

Signed-off-by: Manuel Franceschini <livewire@google.com>
Reviewed-by: Iustin Pop <iustin@google.com>

By changing it to a normal parameter, which must be a sequence, we can
start using keyword parameters.

Before this patch all arguments to “AddTask(self, *args)” were passed as
arguments to the worker's “RunTask” method. Priorities, which should be
optional and will be implemented in a future patch, must be passed as a keyword
parameter. This means “*args” can no longer be used as one can't combine *args
and keyword parameters in a clean way:

>>> def f(name=None, *args):
...   print "%r, %r" % (args, name)
...
>>> f("p1", "p2", "p3", name="thename")
Traceback (most recent call last):
 File "<stdin>", line 1, in <module>
 TypeError: f() got multiple values for keyword argument 'name'

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

Currently, the master IP activation is done in the Exec function. Since
the original masterd process returns after forking, and Exec is run in
the (grand)child process, this means that after 'ganeti-masterd' has
returned there are still initialization tasks running.

Normally this is not a problem, but in cases where one does quick master
failovers, this creates a race condition which hits the QA scripts
especially hard.

To solve this, and make the startup process cleaner (the system is in
steady state after the command has returned, even though masterd startup
could still fail), we move the IP activation to Check(). This also
allows error messages about the IP activation to be seen on the console.

With this patch enabled, I can no longer reproduce the double-failover
errors, which were occuring before in 4/5 cases.

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

This is needed because not just the cli scripts need this decorator, but
the master daemon too (and it already duplicated the code once).

In cli.py we just leave a stub, so that we don't have to modify all the
scripts to import rpc.py.

We then change the master daemon code to reuse this decorator, instead
of duplicating it.

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

Instead of using our custom HTTP client, using PycURL's multi
interface allows us to get rid of the HTTP client threadpool.
The majority of the code is still in the ganeti.http.client
module.

A simple per-thread HTTP client pool gives cURL a chance to
cache and retain as much information as possible (e.g. SSL certs).
Unused HTTP clients (e.g. due to removed nodes) are deleted after
25 requests going through the pool.

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

This patch moves network utility functions to a dedicated module.

Signed-off-by: Manuel Franceschini <livewire@google.com>
Reviewed-by: Iustin Pop <iustin@google.com>

Why it's needed here but not a few lines above is a mistery that only
pylint understands.

Also fix an indentation error in another disable, for the same function.

Signed-off-by: Guido Trotter <ultrotter@google.com>
Reviewed-by: Michael Hanselmann <hansmi@google.com>

Each luxi connection now creates an asyncore MasterClientHandler (which
is an AsyncTerminatedMessageStream subclass, sending each message to a
client worker). This makes it harder to DOS the master daemon by just
creating luxi connections, as each of them will use memory and file
descriptors, but not a dedicated thread.

Each connection will only handle one message at a time.

Signed-off-by: Guido Trotter <ultrotter@google.com>
Reviewed-by: Michael Hanselmann <hansmi@google.com>

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

Not much changes with this patch. The main loop for the IOServer is
repaced by mainloop.Run() and the main thread now uses asyncore to
handle connections to the master socket. Once it accepts them, though,
it just pushes them to the current infrastructure, and everything
proceeds as before.

Signed-off-by: Guido Trotter <ultrotter@google.com>
Reviewed-by: Michael Hanselmann <hansmi@google.com>

Currently the EOM terminator is hardcoded on the server side, and is
customizable in the Transport object (with the default being the same as
the value found in the server), but not in the luxi client.

With this patch we move the value to constants, and remove the "fake"
customizability, which would just break client/server communication. If
we ever need to have a luxi transport with a different terminator it's
easy enough to add it back.

Signed-off-by: Guido Trotter <ultrotter@google.com>
Reviewed-by: Iustin Pop <iustin@google.com>

Ganeti errors should also be logged with a backtrace.

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

This can be very useful if client programs run as non-root.

Signed-off-by: Michael Hanselmann <hansmi@google.com>
Reviewed-by: Guido Trotter <ultrotter@google.com>

Under squeeze pylint reports the following errors:
************* Module ganeti.serializer
E1103:155:LoadSignedJson: Instance of 'False' has no 'get' member (but some types could not be inferred)
************* Module ganeti-masterd
E1103:166:ClientRqHandler.handle: Instance of 'False' has no 'get' member (but some types could not be inferred)
E1103:167:ClientRqHandler.handle: Instance of 'False' has no 'get' member (but some types could not be inferred)
************* Module gnt-instance
E1103:431:BatchCreate: Instance of 'False' has no 'keys' member (but some types could not be inferred)

For the first two cases it's actually wrong: we had checked before that
the variable on which "get" is called is actually a dict. In the third
case though such check doesn't exist, so we add it. Then we silence the
error all three times.

Signed-off-by: Guido Trotter <ultrotter@google.com>
Reviewed-by: Iustin Pop <iustin@google.com>

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Guido Trotter <ultrotter@google.com>

This function could be useful in other places and this
way we can easily unittest it.

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

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

Also fix a typo in http/__init__.py and add unittests
for the LUXI parsing and formatting functions.

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

Having a proper name instead of just a number makes debugging
easier.

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

This changes from submitting jobs to get the tags (in cli scripts) to
queries, which (since the tags query is a cheap one) should be much
faster.

The tags queries are already done without locks (in the generic query
paths for instances/nodes/cluster), so this shouldn't break tags query
via gnt-* list-tags.

On a small cluster, the runtime of gnt-cluster/gnt-instance list tags
more than halves; on a big cluster (with many MCs) I expect it to be
more than 5 times faster. The speed of the tags get is not the main
gain, it is eliminating a job when a simple query is enough.

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

Many of our functions have to follow a given API, and thus we have to
keep a given signature, but pylint doesn't understand this. Therefore,
we silence this warning.

The patch does a few other cleanups.

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Olivier Tharan <olive@google.com>

Of all daemons, only rapi did abort when given argument. None of our
daemons use any arguments, but they accepted them blindly. This is a
very bad experience for the user.

This patch adds checking and exiting in all daemons, in a uniform way.
One other option would have been to add a flag to GenericMain
(noargs=True).

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Olivier Tharan <olive@google.com>

This patch should have only:

- pylint disables
- docstring changes
- whitespace changes

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Olivier Tharan <olive@google.com>

Passing it in as a parameter seems more logical.

Signed-off-by: Michael Hanselmann <hansmi@google.com>
Reviewed-by: Guido Trotter <ultrotter@google.com>

This patch removes the quotes from CommaJoin and converts most of the
callers (that I could find) to it. Since CommaJoin does str(i) for i in
param, we can remove these, thus simplifying slightly a few calls.

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

This is ok because adding a node or instance cannot happen in a query.

We get the ec id from the LU and pass it to _EnsureUUID, which will
then for now not use it.

Signed-off-by: Guido Trotter <ultrotter@google.com>
Reviewed-by: Iustin Pop <iustin@google.com>

When the processor is executing a job, it can export the execution id to
its callers. This is not supported for Queries, as they're not executed
in a job.

Signed-off-by: Guido Trotter <ultrotter@google.com>
Reviewed-by: Iustin Pop <iustin@google.com>

This finishes the conversion of OpPrereqError creation to two-argument
style. Any leftovers as one-argument are not breaking anything, just
losing information about the errors.

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

This is not needed anymore - the original change was more than a year
ago when masterd was in its incipient phase.

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

Currently the luxi error handling is hardcoded as special encoding on
the masterd-side and special decoding on the client side. This patch
moves it to errors.py such that other parts of the code can reuse the
same encoding.

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Michael Hanselmann <hansmi@google.com>
(cherry picked from commit 6956e9cd)

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

This can be useful for debugging locking problems.

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

There are two major arguments for this:
- There will be more callbacks (e.g. for lock debugging) and extending the
  parameter list is a lot of work.
- In the jqueue module this allows us to keep per-job or per-opcode variables in
  a separate class. Instead of having to clean up the worker class after
  processing one job, these references will automatically go out of scope.

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

Signed-off-by: Michael Hanselmann <hansmi@google.com>
Reviewed-by: Guido Trotter <ultrotter@google.com>