Node IDs are currently randomly generated during node startup. That means they change every time the node is restarted. While this doesn't matter for ES proper, it makes it hard for external services to track nodes. Another, more minor, side effect is that indexing the output of, say, the node stats API results in creating new fields due to node ID being used as keys.
The first approach I considered was to use the node's published address as the base for the id. We already [treat nodes with the same address as the same](https://github.com/elastic/elasticsearch/blob/master/core/src/main/java/org/elasticsearch/discovery/zen/NodeJoinController.java#L387) so this is a simple change (see [here](https://github.com/elastic/elasticsearch/compare/master...bleskes:node_persistent_id_based_on_address)). While this is simple and it works for probably most cases, it is not perfect. For example, if after a node restart, the node is not able to bind to the same port (because it's not yet freed by the OS), it will cause the node to still change identity. Also in environments where the host IP can change due to a host restart, identity will not be the same.
Due to those limitation, I opted to go with a different approach where the node id will be persisted in the node's data folder. This has the upside of connecting the id to the nodes data. It also means that the host can be adapted in any way (replace network cards, attach storage to a new VM). I
It does however also have downsides - we now run the risk of two nodes having the same id, if someone copies clones a data folder from one node to another. To mitigate this I changed the semantics of the protection against multiple nodes with the same address to be stricter - it will now reject the incoming join if a node exists with the same id but a different address. Note that if the existing node doesn't respond to pings (i.e., it's not alive) it will be removed and the new node will be accepted when it tries another join.
Last, and most importantly, this change requires that *all* nodes persist data to disk. This is a change from current behavior where only data & master nodes store local files. This is the main reason for marking this PR as breaking.
Other less important notes:
- DummyTransportAddress is removed as we need a unique network address per node. Use `LocalTransportAddress.buildUnique()` instead.
- I renamed `node.add_lid_to_custom_path` to `node.add_lock_id_to_custom_path` to avoid confusion with the node ID which is now part of the `NodeEnvironment` logic.
- I removed the `version` paramater from `MetaDataStateFormat#write` , it wasn't really used and was just in the way :)
- TribeNodes are special in the sense that they do start multiple sub-nodes (previously known as client nodes). Those sub-nodes do not store local files but derive their ID from the parent node id, so they are generated consistently.
This allows `path.shared_data` to be added to the security manager while
still allowing a custom `data_path` for indices using shadow replicas.
For example, configuring `path.shared_data: /tmp/foo`, then created an
index with:
```
POST /myindex
{
"index": {
"number_of_shards": 1,
"number_of_replicas": 1,
"data_path": "/tmp/foo/bar/baz",
"shadow_replicas": true
}
}
```
The index will then reside in `/tmp/foo/bar/baz`.
`path.shared_data` defaults to `null` if not specified.
Resolves#12714
Relates to #11065
Squashed commit of the following:
commit 20835037c98e7d2fac4206c372717a05a27c4790
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 18 15:27:17 2015 -0700
Use Enum for "_primary" preference
commit 325acbe4585179190a959ba3101ee63b99f1931a
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 18 14:32:41 2015 -0700
Use ?preference=_primary automatically for realtime GET operations
commit edd49434af5de7e55928f27a1c9ed0fddb1fb133
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 18 14:32:06 2015 -0700
Move engine creation into protected createNewEngine method
commit 67a797a9235d4aa376ff4af16f3944d907df4577
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 18 13:14:01 2015 -0700
Factor out AssertingSearcher so it can be used by mock Engines
commit 62b0c28df8c23cc0b8205b33f7595c68ff940e2b
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 18 11:43:17 2015 -0700
Use IndexMetaData.isIndexUsingShadowReplicas helper
commit 1a0d45629457578a60ae5bccbeba05acf5d79ddd
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 18 09:59:31 2015 -0700
Rename usesSharedFilesystem -> isOnSharedFilesystem
commit 73c62df4fc7da8a5ed557620a83910d89b313aa1
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 18 09:58:02 2015 -0700
Add MockShadowEngine and hook it up to be used
commit c8e8db473830fce1bdca3c4df80a685e782383bc
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 18 09:45:50 2015 -0700
Clarify comment about pre-defined mappings
commit 60a4d5374af5262bd415f4ef40f635278ed12a03
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 18 09:18:22 2015 -0700
Add a test for shadow replicas that uses field data
commit 7346f9f382f83a21cd2445b3386fe67472bc3184
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 18 08:37:14 2015 -0700
Revert changes to RecoveryTarget.java
commit d90d6980c9b737bd8c0f4339613a5373b1645e95
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 18 08:35:44 2015 -0700
Rename `ownsShard` to `canDeleteShardContent`
commit 23001af834d66278ac84d9a72c37b5d1f3a10a7b
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 18 08:35:25 2015 -0700
Remove ShadowEngineFactory, add .newReadOnlyEngine method in EngineFactory
commit b64fef1d2c5e167713e869b22d388ff479252173
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 18 08:25:19 2015 -0700
Add warning that predefined mappings should be used
commit a1b8b8cf0db49d1bd1aeb84e51491f7f0de43b59
Author: Lee Hinman <lee@writequit.org>
Date: Tue Feb 17 14:31:50 2015 -0700
Remove unused import and fix index creation example in docs
commit 0b1b852365ceafc0df86866ac3a4ffb6988b08e4
Merge: b9d1fed a22bd49
Author: Lee Hinman <lee@writequit.org>
Date: Tue Feb 17 10:56:02 2015 -0700
Merge remote-tracking branch 'refs/remotes/origin/master' into shadow-replicas
commit b9d1fed25ae472a9dce1904eb806702fba4d9786
Merge: 4473e63 41fd4d8
Author: Lee Hinman <lee@writequit.org>
Date: Tue Feb 17 09:02:27 2015 -0700
Merge remote-tracking branch 'refs/remotes/origin/master' into shadow-replicas
commit 4473e630460e2f0ca2a2e2478f3712f39a64c919
Author: Lee Hinman <lee@writequit.org>
Date: Tue Feb 17 09:00:39 2015 -0700
Add asciidoc documentation for shadow replicas
commit eb699c19f04965952ae45e2caf107124837c4654
Author: Simon Willnauer <simonw@apache.org>
Date: Tue Feb 17 16:15:39 2015 +0100
remove last nocommit
commit c5ece6d16d423fbdd36f5d789bd8daa5724d77b0
Author: Simon Willnauer <simonw@apache.org>
Date: Tue Feb 17 16:13:12 2015 +0100
simplify shadow engine
commit 45cd34a12a442080477da3ef14ab2fe7947ea97e
Author: Simon Willnauer <simonw@apache.org>
Date: Tue Feb 17 11:32:57 2015 +0100
fix tests
commit 744f228c192602a6737051571e040731d413ba8b
Author: Simon Willnauer <simonw@apache.org>
Date: Tue Feb 17 11:28:12 2015 +0100
revert changes to IndexShardGateway - these are leftovers from previous iterations
commit 11886b7653dabc23655ec76d112f291301f98f4a
Author: Simon Willnauer <simonw@apache.org>
Date: Tue Feb 17 11:26:48 2015 +0100
Back out non-shared FS code. this will go in in a second iteration
commit 77fba571f150a0ca7fb340603669522c3ed65363
Merge: e8ad614 2e3c6a9
Author: Simon Willnauer <simonw@apache.org>
Date: Tue Feb 17 11:16:46 2015 +0100
Merge branch 'master' into shadow-replicas
Conflicts:
src/main/java/org/elasticsearch/index/engine/Engine.java
commit e8ad61467304e6d175257e389b8406d2a6cf8dba
Merge: 48a700d 1b8d8da
Author: Simon Willnauer <simonw@apache.org>
Date: Tue Feb 17 10:54:20 2015 +0100
Merge branch 'master' into shadow-replicas
commit 48a700d23cff117b8e4851d4008364f92b8272a0
Author: Simon Willnauer <simonw@apache.org>
Date: Tue Feb 17 10:50:59 2015 +0100
add test for failing shadow engine / remove nocommit
commit d77414c5e7b2cde830a8e3f70fe463ccc904d4d0
Author: Simon Willnauer <simonw@apache.org>
Date: Tue Feb 17 10:27:56 2015 +0100
remove nocommits in IndexMetaData
commit abb696563a9e418d3f842a790fcb832f91150be2
Author: Simon Willnauer <simonw@apache.org>
Date: Mon Feb 16 17:05:02 2015 +0100
remove nocommit and simplify delete logic
commit 82b9f0449108cd4741568d9b4495bf6c10a5b019
Author: Simon Willnauer <simonw@apache.org>
Date: Mon Feb 16 16:45:27 2015 +0100
reduce the changes compared to master
commit 28f069b6d99a65e285ac8c821e6a332a1d8eb315
Author: Simon Willnauer <simonw@apache.org>
Date: Mon Feb 16 16:43:46 2015 +0100
fix primary relocation
commit c4c999dd61a44a7a0db9798275a622f2b85b1039
Merge: 2ae80f9 455a85d
Author: Simon Willnauer <simonw@apache.org>
Date: Mon Feb 16 15:04:26 2015 +0100
Merge branch 'master' into shadow-replicas
commit 2ae80f9689346f8fd346a0d3775a6341874d8bef
Author: Lee Hinman <lee@writequit.org>
Date: Fri Feb 13 16:25:34 2015 -0700
throw UnsupportedOperationException on write operations in ShadowEngine
commit 740c28dd9ef987bf56b670fa1a8bcc6de2845819
Merge: e5bc047 305ba33
Author: Lee Hinman <lee@writequit.org>
Date: Fri Feb 13 15:38:39 2015 -0700
Merge branch 'master' into shadow-replicas
commit e5bc047d7c872ae960d397b1ae7b4b78d6a1ea10
Author: Lee Hinman <lee@writequit.org>
Date: Fri Feb 13 11:38:09 2015 -0700
Don't replicate document request when using shadow replicas
commit 213292e0679d8ae1492ea11861178236f4abd8ea
Author: Simon Willnauer <simonw@apache.org>
Date: Fri Feb 13 13:58:05 2015 +0100
add one more nocommit
commit 83d171cf632f9b77cca9de58505f7db8fcda5599
Merge: aea9692 09eb8d1
Author: Simon Willnauer <simonw@apache.org>
Date: Fri Feb 13 13:52:29 2015 +0100
Merge branch 'master' into shadow-replicas
commit aea96920d995dacef294e48e719ba18f1ecf5860
Author: Simon Willnauer <simonw@apache.org>
Date: Fri Feb 13 09:56:41 2015 +0100
revert unneeded changes on Store
commit ea4e3e58dc6959a92c06d5990276268d586735f3
Author: Lee Hinman <lee@writequit.org>
Date: Thu Feb 12 14:26:30 2015 -0700
Add documentation to ShadowIndexShard, remove nocommit
commit 4f71c8d9f706a0c1c39aa3a370efb1604559d928
Author: Lee Hinman <lee@writequit.org>
Date: Thu Feb 12 14:17:22 2015 -0700
Add documentation to ShadowEngine
commit 28a9d1842722acba7ea69e0fa65200444532a30c
Author: Lee Hinman <lee@writequit.org>
Date: Thu Feb 12 14:08:25 2015 -0700
Remove nocommit, document canDeleteIndexContents
commit d8d59dbf6d0525cd823d97268d035820e5727ac9
Author: Lee Hinman <lee@writequit.org>
Date: Thu Feb 12 10:34:32 2015 -0700
Refactor more shared methods into the abstract Engine
commit a7eb53c1e8b8fbfd9281b43ae39eacbe3cd1a0a6
Author: Simon Willnauer <simonw@apache.org>
Date: Thu Feb 12 17:38:59 2015 +0100
Simplify shared filesystem recovery by using a dedicated recovery handler that skip
most phases and enforces shard closing on the soruce before the target opens it's engine
commit a62b9a70adad87d7492c526f4daf868cb05018d9
Author: Simon Willnauer <simonw@apache.org>
Date: Thu Feb 12 15:59:54 2015 +0100
fix compile error after upstream changes
commit abda7807bc3328a89fd783ca7ad8c6deac35f16f
Merge: f229719 35f6496
Author: Simon Willnauer <simonw@apache.org>
Date: Thu Feb 12 15:57:28 2015 +0100
Merge branch 'master' into shadow-replicas
Conflicts:
src/main/java/org/elasticsearch/index/engine/Engine.java
commit f2297199b7dd5d3f9f1f109d0ddf3dd83390b0d1
Author: Simon Willnauer <simonw@apache.org>
Date: Thu Feb 12 12:41:32 2015 +0100
first cut at catchup from primary
make flush to a refresh
factor our ShadowIndexShard to have IndexShard be idential to the master and least intrusive
cleanup abstractions
commit 4a367c07505b84b452807a58890f1cbe21711f27
Author: Simon Willnauer <simonw@apache.org>
Date: Thu Feb 12 09:50:36 2015 +0100
fix primary promotion
commit cf2fb807e7e243f1ad603a79bc9d5f31a499b769
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 11 16:45:41 2015 -0700
Make assertPathHasBeenCleared recursive
commit 5689b7d2f84ca1c41e4459030af56cb9c0151eff
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 11 15:58:19 2015 -0700
Add testShadowReplicaNaturalRelocation
commit fdbe4133537eaeb768747c2200cfc91878afeb97
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 11 15:28:57 2015 -0700
Use check for shared filesystem in primary -> primary relocation
Also adds a nocommit
commit 06e2eb4496762130af87ce68a47d360962091697
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 11 15:21:32 2015 -0700
Add a test checking that indices with shadow replicas clean up after themselves
commit e4dbfb09a689b449f0edf6ee24222d7eaba2a215
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 11 15:08:18 2015 -0700
Fix segment info for ShadowEngine, remove test nocommit
commit 80cf0e884c66eda7d59ac5d59235e1ce215af8f5
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 11 14:30:13 2015 -0700
Remove nocommit in ShadowEngineTests#testFailStart()
commit 5e33eeaca971807b342f9be51a6a566eee005251
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 11 14:22:59 2015 -0700
Remove overly-complex test
commit 2378fbb917b467e79c0262d7a41c23321bbeb147
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 11 13:45:44 2015 -0700
Fix missing import
commit 52e9cd1b8334a5dd228d5d68bd03fd0040e9c8e9
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 11 13:45:05 2015 -0700
Add a test for replica -> primary promotion
commit a95adbeded426d7f69f6ddc4cbd6712b6f6380b4
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 11 12:54:14 2015 -0700
Remove tests that don't apply to ShadowEngine
commit 1896feda9de69e4f9cf774ef6748a5c50e953946
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 11 10:29:12 2015 -0700
Add testShadowEngineIgnoresWriteOperations and testSearchResultRelease
commit 67d7df41eac5e10a1dd63ddb31de74e326e9d38b
Author: Lee Hinman <lee@writequit.org>
Date: Wed Feb 11 10:06:05 2015 -0700
Add start of ShadowEngine unit tests
commit ca9beb2d93d9b5af9aa6c75dbc0ead4ef57e220d
Merge: 2d42736 57a4646
Author: Simon Willnauer <simonw@apache.org>
Date: Wed Feb 11 18:03:53 2015 +0100
Merge branch 'master' into shadow-replicas
commit 2d42736fed3ed8afda7e4aff10b65d292e1c6f92
Author: Simon Willnauer <simonw@apache.org>
Date: Wed Feb 11 17:51:22 2015 +0100
shortcut recovery if we are on a shared FS - no need to compare files etc.
commit 24d36c92dd82adce650e7ac8e9f0b43c83b2dc53
Author: Simon Willnauer <simonw@apache.org>
Date: Wed Feb 11 17:08:08 2015 +0100
utilize the new delete code
commit 2a2eed10f58825aae29ffe4cf01aefa5743a97c7
Merge: 343dc0b 173cfc1
Author: Simon Willnauer <simonw@apache.org>
Date: Wed Feb 11 16:07:41 2015 +0100
Merge branch 'master' into shadow-replicas
Conflicts:
src/main/java/org/elasticsearch/gateway/GatewayMetaState.java
commit 343dc0b527a7052acdc783ac5abcaad1ef78dbda
Author: Simon Willnauer <simonw@apache.org>
Date: Wed Feb 11 16:05:28 2015 +0100
long adder is not available in java7
commit be02cabfeebaea74b51b212957a2a466cfbfb716
Author: Lee Hinman <lee@writequit.org>
Date: Tue Feb 10 22:04:24 2015 -0700
Add test that restarts nodes to ensure shadow replicas recover
commit 7fcb373f0617050ca1a5a577b8cf32e32dc612b0
Author: Simon Willnauer <simonw@apache.org>
Date: Tue Feb 10 23:19:21 2015 +0100
make test more evil
commit 38135af0c1991b88f168ece0efb72ffe9498ff59
Author: Simon Willnauer <simonw@apache.org>
Date: Tue Feb 10 22:25:11 2015 +0100
make tests pass
commit 05975af69e6db63cb95f3e40d25bfa7174e006ea
Author: Lee Hinman <lee@writequit.org>
Date: Mon Jan 12 18:44:29 2015 +0100
Add ShadowEngine
Boaz Leskes
Lee Hinman
Yannick Welsch