This commit modifies the follow stats API response structure to more
clearly highlight meaning of the higher level fields. In particular,
previously the response had a top-level key for each index. Instead, we
nest the indices under an "indices" field which is now an array. The
values in this array are objects containing two fields: "index" which is
the name of the follower index, and "shards" which is an array where
each value in the array is the follower stats for that shard. That is,
we have gone from:
{
"bar": [
{
"shard_id": 0...
}...
]...
}
to
{
"indices": [
{
"index": "bar",
"shards": [
{
"shard_id": 0...
}...
]
}...
}
In the CCR docs we want to refer to the endpoint that returns following
stats as the follow stats API. This commit renames the internal
implementation of this endpoint to reflect this usage.
The follower index shard history UUID will be fetched from the indices stats api when the shard follow task starts and will be provided with the bulk shard operation requests. The bulk shard operations api will fail if the provided history uuid is unequal to the actual history uuid.
No longer record the leader history uuid in shard follow task params, but rather use the leader history UUIDs directly from follower index's custom metadata. The resume follow api will remain to fail if leader index shard history UUIDs are missing.
Closes#33956
Since #34099, the FollowingEngine will skip an operation which was
already processed before. With that change, it should be okay to unmute
testFollowIndexAndCloseNode.
This arose when two commits were pushed at roughly the same time, both
of which compiled successfully against master, but not when taken
together. This commit fixes a reference in one of the commits that was
changed in the other commit.
This commit modifies the CCR stats endpoint for indices to be
/{index}/_ccr/stats. This makes this endpoint consistent with other
index-centric endpoints like indices stats.
The unfollow API changes a follower index into a regular index, so that it will accept write requests from clients.
For the unfollow api to work the index follow needs to be stopped and the index needs to be closed.
Closes#33931
This change introduces the indexing optimization using sequence numbers
in the FollowingEngine. This optimization uses the max_seq_no_updates
which is tracked on the primary of the leader and replicated to replicas
and followers.
Relates #33656
Prior to following an index in the follow API, check whether current
user has sufficient privileges in the leader cluster to read and
monitor the leader index.
Also check this in the create and follow API prior to creating the
follow index.
Also introduced READ_CCR cluster privilege that include the minimal
cluster level actions that are required for ccr in the leader cluster.
So a user can follow indices in a cluster, but not use the ccr admin APIs.
Closes#33553
Co-authored-by: Jason Tedor <jason@tedor.me>
The following changes were made:
* Added ElasticsearchSecurityException. For in the case the current user has insufficient privileges while an index is being followed. Prior to following ccr checks whether the current user has sufficient privileges and if not the follow api fails with an error.
* Added Index block exception. If the leader index gets closed, this exception is returned.
* Added ClusterBlockException service unavailable. In case for example the leader cluster is without elected master.
* Removed IndexNotFoundException. If the leader / follower index has been deleted, ccr will need to stop the shard follow tasks with an error.
Closes#33954
* Renamed CCR APIs
Renamed:
* `/{index}/_ccr/create_and_follow` to `/{index}/_ccr/follow`
* `/{index}/_ccr/unfollow` to `/{index}/_ccr/pause_follow`
* `/{index}/_ccr/follow` to `/{index}/_ccr/resume_follow`
Relates to #33931
always use `IndicesOptions.strictExpand()` for indices options.
The follow index may be closed and we still want to get stats from
shard follow task and the whether the provided index name matches with
follow index name is checked when locating the task itself in the ccr
stats transport action.
This commit replicates the max_seq_no_of_updates on the leading index
to the primaries of the following index via ShardFollowNodeTask. The
max_seq_of_updates is then transmitted to the replicas of the follower
via replication requests (that's BulkShardOperationsRequest).
Relates #33656
We start tracking max seq_no_of_updates on the primary in #33842. This
commit replicates that value from a primary to its replicas in replication
requests or the translog phase of peer-recovery.
With this change, we guarantee that the value of max seq_no_of_updates
on a replica when any index/delete operation is performed at least the
max_seq_no_of_updates on the primary when that operation was executed.
Relates #33656
If numWrites is between 2 and 9, we will issue an invalid range because
the from_seq_no is negative. This commit makes sure that numWrites is at
least 10, and adds an explicit test to verify invalid request ranges.
This PR is the first step to use seq_no to optimize indexing operations.
The idea is to track the max seq_no of either update or delete ops on a
primary, and transfer this information to replicas, and replicas use it
to optimize indexing plan for index operations (with assigned seq_no).
The max_seq_no_of_updates on primary is initialized once when a primary
finishes its local recovery or peer recovery in relocation or being
promoted. After that, the max_seq_no_of_updates is only advanced internally
inside an engine when processing update or delete operations.
Relates #33656
Instead of having one constructor that accepts all arguments, all parameters
should be provided via setters. Only leader and follower index are required
arguments. This makes using this class in tests and transport client easier.
The following stats are being kept track of:
1) The total number of times that auto following a leader index succeed.
2) The total number of times that auto following a leader index failed.
3) The total number of times that fetching a remote cluster state failed.
4) The most recent 256 auto follow failures per auto leader index
(e.g. create_and_follow api call fails) or cluster alias
(e.g. fetching remote cluster state fails).
Each auto follow run now produces a result that is being used to update
the stats being kept track of in AutoFollowCoordinator.
Relates to #33007
* [CCR] Do not unnecessarily wrap fetch exception in a ElasticSearch exception and
properly map fetch_exception.exception field as object.
The extra caused by level is not necessary here:
```
"fetch_exceptions": [
{
"from_seq_no": 1,
"retries": 106,
"exception": {
"type": "exception",
"reason": "[index1] IndexNotFoundException[no such index]",
"caused_by": {
"type": "index_not_found_exception",
"reason": "no such index",
"index_uuid": "_na_",
"index": "index1"
}
}
}
],
```
When a leader index is created, it may not have a mapping yet.
Currently if you follow such an index the shard follow tasks fail with
NoSuchElementException, because they expect a single mapping.
This commit fixes that, by allowing that a leader index does not yet have
a mapping.
Rather than scheduling pings to the leader index when we are caught up
to the leader, this commit introduces long polling for changes. We will
fire off a request to the leader which if we are already caught up will
enter a poll on the leader side to listen for global checkpoint
changes. These polls will timeout after a default of one minute, but can
also be specified when creating the following task. We use these time
outs as a way to keep statistics up to date, to not exaggerate time
since last fetches, and to avoid pipes being broken.
When executing CCR REST tests it is going to be expected after global
checkpoint polling goes in that shard changes tasks can still be pending
at the end of the test. One way to deal with this is to set a low
timeout on these polls, but then that means we are not executing our
REST tests with our default production settings and instead would be
using an unrealistic low timeout. Alternatively, since we expect these
tasks to be there, we can not count them against the test. That is what
this commit does.
This commit moves these REST tests (possibly temporarily) to a
sub-project of ccr. We do this (again, possibly temporarily) to keep
them within the ccr sub-project yet there are changes within 6.x that
prevent these from being in the top-level project (the cluster formation
tasks are trying to install x-pack-ccr into the
integ-test-zip). Therefore, we isolate these for now until we can
understand why there are differences between 6.x and master.
When developing ccr it is not ideal if tests are in multiple modules.
Even the classes these tests test are in the core module, it is easier
if these tests are in ccr module in order to avoid running the test task
in core module. This results in running many non ccr tests.
This way when developing ccr we can run locally:
./gradlew x-pack:plugin:core:precommit x-pack:plugin:ccr:check
before pushing to PR branches and be confident that the PR build passes,
without running x-pack:plugin:core:check task.
and if so debug log it and otherwise rethrow.
This should fix a couple of test failures where during test teardown tests
failed due to uncaught exceptions being detected.
Jason Tedor
Nhat Nguyen
Martijn van Groningen