Configurations employing shared-storage with NFS are susceptible to
split-brain in certain scenarios. For example:
1) Primary loses network connection to NFS.
2) Backup activates.
3) Primary reconnects to NFS.
4) Split-brain.
In reality this situation is pretty unlikely due to the timing involved,
but the possibility still exists. Currently the file lock held by the
primary broker on the NFS share is essentially worthless in this
situation. This commit adds logic by which the timestamp of the lock
file is updated during activation and then routinely checked during
runtime to ensure consistency. This effectively mitigates split-brain in
this situation (and likely others). Here's how it works now.
1) Primary loses network connection to NFS.
2) Backup activates.
3) Primary reconnects to NFS.
4) Primary detects that the lock file's timestamp has been updated and
shuts itself down.
When the primary shuts down in step #4 the Topology on the backup can be
damaged. Protections were added for this via ARTEMIS-2868 but only for
the replicated use-case. This commit applies the protection for
removeMember() so that the Topology remains intact.
There are no tests for these changes as I cannot determine how to
properly simulate this use-case. However, there have never been robust,
automated tests for these kinds of NFS use-cases so this is not a
departure from the norm.
For pipelined open cases the events processing should ignore additional begin
and attach events if the open event handler closes the connection to avoid the
processing throwing additional exceptions and replacing the error condition in
the connection with an unrelated error about NPE from the additional events.
I am adding three attributes to Address-settings:
* page-limit-bytes: Number of bytes. We will convert this metric into max number of pages internally by dividing max-bytes / page-size. It will allow a max based on an estimate.
* page-limit-messages: Number of messages
* page-full-message-policy: fail or drop
We will now allow paging, until these max values and then fail or drop messages.
Once these values are retracted, the address will remain full until a period where cleanup is kicked in by paging. So these values may have a certain delay on being applied, but they should always be cleared once cleanup happened.
Moves embedded XSD element definitions and associated complexTypes
from XSD element definitions to top-level types available for XML
schema validation in IDEs.
o.a.a.a.c.p.m.MQTTSubscriptionManager#removeSubscription() had a chunk
of code from 971f673c60 removed. That code
was added under the assumption that there should only ever be one
consumer per queue. That was true for MQTT 3.x, but it's not always true
for MQTT 5 due to shared subscriptions. However, the tests from that
commit all still pass even with it removed now (as well as all the other
MQTT tests) so I think it's safe.
If the client is using address prefixes to define the routing type along with
durable subscriptions then on re-attach the compairon to check if the subscription
address has changed needs to remove the prefix when comparing against the address
since the prefix isn't propagated when creating the address and will always fail
resulting in the subscription queue being deleted in error.
Adds some tests to validate that the destination prefixes if set and
are used properly by the client are honored over the default address
auto create routing type condiguration.
When an AMQP client subscribes to a new address (non-existing) with a receiver link, the
address is created with routing type ANYCAST regardles of the default address creation
configuration of the broker, and ignores even the broker wide default of MULTICAST.
I am adding an option sync=true or false on mirror. if sync, any client blocking operation will wait a roundtrip to the mirror
acting like a sync replica.
Justin Bertram
ALX
Rakhi Kumari
Clebert Suconic
Gary Tully
Ryan Highley
Timothy Bish
Robbie Gemmell
Domenico Francesco Bruscino
Erwin Dondorp
iliya
Andy Taylor