Release Notes for MongoDB 5.0
On this page
- Patch Releases
- Time Series Collections
- Aggregation
- Auditing
- Capped Collections
- Change Streams
- Indexes
- Removed Commands
- Replica Sets
- Security
- Sharded Clusters
- Shell Changes
- Snapshots
- Transactions
- Naming Changes
- General Changes
- Performance Considerations
- Platform Support
- Changes Affecting Compatibility
- Upgrade Procedures
- Downgrade Consideration
- Download
- Known Issues
- Report an Issue
Note
MongoDB 5.0 Released July 13, 2021
Patch Releases
Warning
Past Release Limitations
The Critical Advisories below affect some prior MongoDB versions. If your deployment depends on features impacted by a Critical Advisory, upgrade to the latest available patch release.
Issue | Affected Versions |
---|---|
5.0.0 - 5.0.2 | |
5.0.0 - 5.0.2 | |
5.0.0 - 5.0.14 (ARM64 or POWER system architectures) | |
5.0.2 - 5.0.17 (Incremental backups on Ops Manager or Cloud Manager clusters) | |
5.0.0 - 5.0.1 | |
5.0.0 - 5.0.21 | |
5.0.0 - 5.0.10 | |
5.0.0 - 5.0.23 | |
5.0.6 - 5.0.21 (Time Series collections sharded by metaField embedded objects) | |
5.0.0 - 5.0.24 |
5.0.30 - Oct 24, 2024
Important
Improper neutralization of null bytes may lead to buffer over-reads in MongoDB Server
In MongoDB 5.0 prior to 5.0.30, an authorized user may trigger crashes or receive the contents of buffer over-reads of Server memory by issuing specially crafted requests that construct malformed BSON in the MongoDB Server.
This issue affects MongoDB Server versions:
5.0.0 - 5.0.29
6.0.0 - 6.0.18
7.0.0 - 7.0.14
8.0.0 - 8.0.1
SERVER-96419 Improper neutralization of null bytes may lead to buffer over-reads in MongoDB Server
5.0.29 - Sep 30, 2024
Important
Fix for CSFLE and Queryable Encryption self-lookup may send values in subpipelines as plaintext instead of ciphertext
Due to CVE-2024-8013, in MongoDB 5.0 prior to 5.0.28, a bug in query analysis of
certain complex self-referential $lookup
subpipelines
may result in literal values in expressions for encrypted fields
being sent to the server malformed.
Should this occur, no documents are returned or written.
This issue affects the mongocryptd
binary and mongo_crypt_v1
shared library in the following MongoDB Server versions:
7.3.0 - 7.3.3
7.0.0 - 7.0.11
6.0.0 - 6.0.16
5.0.0 - 5.0.28
CVSS Score: 2.2
CWE: CWE-319: Cleartext Transmission of Sensitive Information
SERVER-96254 CSFLE and Queryable Encryption self-lookup may fail to encrypt values in subpipelines
SERVER-59831 WTUniqueIndex::_insert expects secondaries to pass in dupsAllowed=true
SERVER-76777 Deadlock between index build external abort and self abort
SERVER-88750 Add "bypassEmptyTsReplacement" param to insert, update, findAndModify, and bulkWrite
SERVER-91223 $log gives incorrect calculation with Decimal128
WT-8771 Checkpoint cleanup to dirty obsolete page with overflow items
5.0.28 - Jul 15, 2024
SERVER-63198 Prevent shutdown command from hanging
SERVER-90747 Handle $elemMatch with empty path in plan enumerator correctly
SERVER-91362 Performance: Do not copy JS "scope" object if a cached JsExecution exists
SERVER-91562 [5.0] IndexDescriptor::compareIndexOptions treats no unique/sparse as not identical to unique:false/sparse:false
WT-10807 Skip in-memory deleted pages as part of the tree walk
5.0.27 - Jun 04, 2024
SERVER-78556 Return default of internalInsertMaxBatchSize to 64
SERVER-79637 Incorrect query results in $lookup with TS foreign collection using a correlated predicate
SERVER-80363 server default writeConcern is not honored when wtimeout is set
SERVER-86474 $_internalApplyOplogUpdate with $set: { foo: Timestamp(0, 0) } is not replicated correctly
SERVER-86648 Resumable index build sorter files are not fsynced on shutdown
5.0.26 - Mar 26, 2024
SERVER-68128 Exceptions thrown while generating command response lead to network error
SERVER-72703 Downgrade $out's db lock to MODE_IX
SERVER-83602 $or -> $in MatchExpression rewrite should not generate $or directly nested in another $or
SERVER-86717 Resharding should validate user provided zone range doesn't include $-prefixed fields.
WT-11062 Safe free the ref addr to allow concurrent access
5.0.25 - Feb 28, 2024
Important
Fix for MongoDB Server may allow successful untrusted connection
Due to CVE-2024-1351, in MongoDB 5.0 prior to 5.0.25, under certain
configurations of --tlsCAFile
and
CAFile
, MongoDB Server may skip peer certificate
validation which may result in untrusted connections to succeed.
This may effectively reduce the security guarantees provided by TLS and open connections that should have been closed due to failing certificate validation. This issue affects the following MongoDB Server versions:
7.0.0 - 7.0.5
6.0.0 - 6.0.13
5.0.0 - 5.0.24
4.4.0 - 4.4.28
CVSS Score: 8.8
CWE: CWE-295: Improper Certificate Validation
SERVER-64444 listIndexes fails on invalid pre-5.0 index spec after upgrade
SERVER-82353 Multi-document transactions can miss documents when movePrimary runs concurrently
SERVER-83564 Make sure the process field is indexed in config.locks
SERVER-85419 Balancer pollutes logs in case no suitable recipient is found during draining
WT-10017 Remove the unstable historical versions at the end of rollback to stable
5.0.24 - Jan 18, 2024
SERVER-50792 Return more useful errors when a shard key index can't be found for shardCollection/refineCollectionShardKey
SERVER-77506 Sharded multi-document transactions can mismatch data and ShardVersion
SERVER-81878 startupRecoveryForRestore may not play nicely with collection drop applied during startup recovery
SERVER-83091 $or query can trigger an infinite loop during plan enumeration
WT-7929 Investigate a solution to avoid FTDC stalls during checkpoint
5.0.23 - Nov 27, 2023
SERVER-78108 POS interface should expose its shutdown state
SERVER-78115 Shard primaries must commit a majority write before using new routing information from the config server
SERVER-83150 Document::shred() does not copy document metadata
WT-11564 Fix RTS to read the newest transaction value only when it exists in the checkpoint
WT-11602 Hide expected eviction failures from the application and don't rollback in case of errors
5.0.22 - Oct 26, 2023
SERVER-68548 MongoDB Shell version 4.4.15 logging asio message despite --quiet flag
SERVER-80021 Make $convert round-trip correctly between double and string
SERVER-80703 Avoid traversing routing table in MigrationDestinationManager
SERVER-81106 Recipient shard doesn't wait for the collection version to be locally persisted before starting the cloning phase
WT-11064 Skip globally visible tombstones as part of update obsolete check
5.0.21 - Sep 12, 2023
SERVER-60466 Support drivers gossiping signed $clusterTimes to replica set --shardsvrs before addShard is run
SERVER-71627 Refreshed cached collection route info will severely block all client request when a cluster with 1 million chunks
SERVER-78813 Commit point propagation fails indefinitely with exhaust cursors with null lastCommitted optime
WT-10759 Do not retry to force evict history store pages during reconciliation
WT-11051 Fix newest start durable timestamp comparison in aggregate timestamp validation
5.0.20 - Aug 14, 2023
SERVER-74954 Incorrect result when contained $or rewrites $elemMatch extra condition
SERVER-78813 Commit point propagation fails indefinitely with exhaust cursors with null lastCommitted optime
SERVER-79136 Incorrect query result of $match + $group on metaField over time-series
WT-10449 Do not save update chain when there are no updates to be written to the history store
WT-11031 Fix RTS to skip tables with no time window information in the checkpoint
5.0.19 - Jul 13, 2023
SERVER-71985 Automatically retry time series insert on DuplicateKey error
SERVER-74551 WriteConflictException unnecessarily logged as warning during findAndModify after upgrade to mongo 5.0
SERVER-77018 Deadlock between dbStats and 2 index builds
SERVER-78126 For specific kinds of input, mongo::Value() always hashes to the same result on big-endian platforms
WT-10253 Run session dhandle sweep and session cursor sweep more often
5.0.18 - May 18, 2023
Issues fixed:
SERVER-48196 Upgrade the timelib to the latest to update the built-in timezone files to the latest
SERVER-54150 Recovery from a stable checkpoint should fassert on oplog application failures
SERVER-57056 Syslog severity set incorrectly for INFO messages
SERVER-72686 Add support for $collStats agg stage on timeseries collection
WT-10551 Incremental backup may omit modified blocks
5.0.17 - Apr 27, 2023
Issues fixed:
SERVER-73229 Logical sessions cache refresh ignores write errors from updating session document, leading to cursors being killed early
SERVER-74647 Resharding state machine creation should be retried after interruption
SERVER-75261 "listCollections" command fails with BSONObjectTooLarge error
SERVER-75431 Get rid or fix best effort check for primary db on rename path in sharded clusters
SERVER-76098 Allow queries with $search and non-simple collations
5.0.16 - Apr 10, 2023
Issues fixed:
SERVER-61909 Hang inserting or deleting document with large number of index entries
SERVER-73822 Time-series $group rewrite ignores certain accumulators
SERVER-74345 mongodb-org-server 4.4.19, 5.0.15, 6.0.5 not starting after upgrading from older version (Debian, RPM Packages)
SERVER-74501 Fix MigrationBatchFetcher/Inserter completion reliance to not spawn an extra cleanup thread
SERVER-75205 Deadlock between stepdown and restoring locks after yielding when all read tickets exhausted
5.0.15 - Feb 27, 2023
Issues fixed:
SERVER-54900 Blocking networking calls can delay sync-source resolution indefinitely
SERVER-72416 The find and findAndModify projection code does not honor the collection level collation
SERVER-71759 dataSize command doesn't yield
SERVER-72222 MapReduce with single reduce optimization fails when merging results in sharded cluster
WT-9268 Delay deletion of the history store record to reconciliation
5.0.14 - Nov 21, 2022
Issues fixed:
SERVER-68477 Improve NaN-handling for expireAfterSeconds TTL index parameter
SERVER-66289 $out incorrectly throws BSONObj size error on v5.0.8
SERVER-61185 Use prefix_search for unique index lookup
SERVER-68115 Bug fix for "elemMatchRootLength > 0" invariant trigger
SERVER-68139 Resharding command fails if the projection sort is bigger than 100MB
5.0.13 - Sep 29, 2022
Issues fixed:
SERVER-69611 Set the -ffp-contract=off compiler option by default
SERVER-69220 refineCollectionShardKey permits toggling current shard key fields between range-based and hashed, leading to data inconsistency
SERVER-67650 Resharding recipient can return remainingOperationTimeEstimatedSecs=0 when the oplog applier hasn't caught up with the oplog fetcher
SERVER-68094 Resharding with custom generated _id fails with projection error
WT-9870 Fix updating pinned timestamp whenever oldest timestamp is updated during recovery
5.0.12 - Sep 05, 2022
Issues fixed:
SERVER-68925 Reintroduce check table logging settings at startup (revert SERVER-43664)
SERVER-63852 getThreadName() should not crash
SERVER-60958 Avoid server hang in chunk migration when step-down event occurs
SERVER-65382 AutoSplitVector should not use clientReadable to reorder shard key fields
SERVER-63843 Don't allow recursive doLog in synchronous signal handlers
5.0.11 - Aug 19, 2022
Issues fixed:
SERVER-68511 MovePrimary update of
config.databases
entry must use dotted fields notationSERVER-61321 Improve handling of large/NaN values for text index version
SERVER-60607 Improve handling of large/NaN values for geo index version
SERVER-68628 Retrying a failed resharding operation after a primary failover can lead to server crash or lost writes
SERVER-68522 Prevent 5.0 binary from starting in fCV 4.4 with misconfigured TTL index
WT-9500 Fix RTS to use cell time window instead of key/value timestamps of HS update
5.0.10 - Jul 29, 2022
Issues fixed:
SERVER-66418 Bad projection created during dependency analysis due to string order assumption
SERVER-65821 Deadlock during setFCV when there are prepared transactions that have not persisted commit/abort decision
SERVER-65131 Disable opportunistic read targeting (except for hedged reads)
SERVER-63971 Change server parameter to default to read-your-writes behavior after 2PC transaction
SERVER-66433 Backport deadline waiting for overlapping range deletion to finish to pre-v5.1 versions
5.0.9 - May 31, 2022
Issues fixed:
SERVER-65636 Remove limits on number of LDAP connections per host
SERVER-65137 Detect namespace changes when refreshing Collection after yielding
SERVER-64822 Sharding an empty collection releases the critical section too early
SERVER-62175 Mongos fails to attach RetryableWrite Error Label For Command Interrupted In _parseCommand
WT-9096 Fix search near returning wrong key/value sometimes when key doesn't exist
5.0.8 - Apr 25, 2022
Issues fixed:
SERVER-63531 commitQuorum incorrectly includes buildIndexes:false nodes and error message incorrectly says that only voting nodes are eligible
SERVER-63387 1 StreamingCursor should return backup blocks in the order they were retrieved from the WiredTiger backup cursor
SERVER-62229 Fix invariant when applying index build entries while recoverFromOplogAsStandalone=true
SERVER-61879 Refreshes to recover migrations must never join ongoing refreshes
WT-8924 Don't check against on disk time window if there is an insert list when checking for conflicts in row-store
5.0.7 - Apr 11, 2022
Issues fixed:
SERVER-64517 RecoverableCriticalSection is not properly recovered on startup
SERVER-64403 Find queries with SORT_MERGE collation-encode the missing sort attribute
SERVER-63742 Default topology time in shard can lead to infinite refresh in shard registry
SERVER-60412 Host memory limit check does not honor cgroups v2
WT-7922 Handle missing WiredTiger version file
5.0.6 - Jan 31, 2022
Issues fixed:
WT-8395 Inconsistent data after upgrade from 4.4.3 and 4.4.4 to 4.4.8+ and 5.0.2+
SERVER-62245 MigrationRecovery must not assume that only one migration needs to be recovered
SERVER-61427 Unique index builds can cause a loss of availability during commit due to checking many false duplicates
SERVER-61194 Prevent time-series bucket OID reuse with coarse granularity
SERVER-60310 OCSP response validation should not consider statuses of irrelevant certificates
5.0.5 - Dec 6, 2021
Issues fixed:
SERVER-61483 Resharding coordinator fails to recover abort decision on step-up, attempts to commit operation as success, leading to data inconsistency
SERVER-59858 Add observability for tasks scheduled on the reactor thread
SERVER-51329 Unexpected non-retryable error when shutting down a mongos server
WT-8163 Consider more eviction scenarios to give up checkpoint-cleanup
WT-7912 Fix prefix search near optimisation to handle scenarios where the key range is split across pages.
5.0.4 - Nov 15, 2021
Issues fixed:
SERVER-60326 Windows Server fails to start when X509 certificate has empty subject name
SERVER-59876 Large delays in returning from libcrypto.so while establishing egress connections
SERVER-59456 Start the LDAPReaper threadpool
SERVER-59226 Deadlock when stepping down with a profile session marked as uninterruptible
SERVER-59074 Do not acquire storage tickets just to set/wait on oplog visibility
5.0.3 - Sep 21, 2021
Issues fixed:
SERVER-57667: Improve processing speed for resharding's collection cloning pipeline
SERVER-57630: Enable SSL_OP_NO_RENEGOTIATION on Ubuntu 18.04 when running against OpenSSL 1.1.1
WT-8005: Fix a prepare commit bug that could leave the history store entry unresolved
WT-7995: Fix the global visibility that it cannot go beyond checkpoint visibility
WT-7984: Fix a bug that could cause a checkpoint to omit a page of data
5.0.2 - Aug 4, 2021
Issues fixed:
SERVER-58936: Unique index constraints may not be enforced
SERVER-57756: Race between concurrent stepdowns and applying transaction oplog entry
SERVER-54729: MongoDB Enterprise Debian/Ubuntu packages should depend on libsasl2-modules and libsasl2-modules-gssapi-mit
SERVER-47372: config.cache collections can remain even after collection has been dropped
WT-6729: Quiesce eviction prior running rollback to stable's active transaction check
5.0.1 - Jul 22, 2021
Issues fixed:
SERVER-58489: Collection creation stuck in an infinite writeConflictRetry loop when having a duplicate name as a view
SERVER-58171: Changing time-series granularity does not update view definition
5.0.0 - Jul 13, 2021
The rest of this page provides the 5.0.0 release notes:
Time Series Collections
MongoDB 5.0 introduces time series collections which efficiently store sequences of measurements over a period of time. Compared to normal collections, storing time series data in time series collections improves query efficiency and reduces disk usage for your data and indexes.
Aggregation
New Aggregation Operators
MongoDB 5.0 introduces the following aggregation operators:
Operator | Description |
---|---|
The | |
Increments a | |
Returns the difference between two dates. | |
Decrements a | |
Truncates a date. | |
Returns the value of a specified field from a document.
You can use | |
The | |
Adds the | |
Adds, updates, or removes a specified field in a document.
You can use | |
Removes a specified field in a document. An alias for
|
Window Operators
MongoDB 5.0 introduces the $setWindowFields
pipeline stage,
allowing you to perform operations on a specified span of documents in a
collection, known as a window. The operation returns the results based
on the chosen window operator.
For example, you can use the $setWindowFields
stage to
output the:
Difference in sales between two documents in a collection.
Sales rankings.
Cumulative sales totals.
Analysis of complex time series information without exporting the data to an external database.
General Aggregation Improvements
$expr
Operator: Comparison Operators Use Indexes
Starting in MongoDB 5.0, the $eq
, $lt
,
$lte
, $gt
, and $gte
operators
placed in an $expr
operator can use indexes to improve performance.
$ifNull
Expression Accepts Multiple Input Expressions
Starting in MongoDB 5.0, you can specify multiple input expressions for
the $ifNull
expression before returning a replacement
expression.
let
Option for Aggregation
Starting in MongoDB 5.0, the aggregate
command and
db.collection.aggregate()
helper method have a let
option
to specify a list of variables that can be used elsewhere in the
aggregation pipeline. This allows you to improve command readability by
separating the variables from the query text.
$lookup
Stage: Concise Correlated Subqueries
Starting in MongoDB 5.0, an aggregation pipeline $lookup
stage supports concise correlated subqueries that improve joins between
collections.
$lookup
Stage: Uncorrelated Subqueries
Starting in MongoDB 5.0, for an uncorrelated subquery in a
$lookup
pipeline stage containing a $sample
stage, the $sampleRate
operator, or the
$rand
operator, the subquery is always run again if
repeated. Previously, depending on the subquery output size, either the
subquery output was cached or the subquery was run again.
$sort
Stage: Performance Improvements
Starting in MongoDB 5.0, the query optimizer pushes down the results of
a $project
stage into the $sort
stage. As a result,
$sort
operations can require less RAM when used with the project
stage
and avoid Sort exceeded memory limit
errors.
Auditing
Runtime Audit Filter Configuration
MongoDB 5.0 adds the ability to configure auditing filters at runtime.
Operator | Description |
---|---|
Defines the polling interval for checking audit configuration | |
General Auditing Updates
Starting in MongoDB 5.0:
An additional uuid field and other audit message enhancements.
New audit message types: clientMetadata, directAuthMutation, logout, and startup.
Additional information and logging scenarios for these existing audit message types: authCheck, authenticate, createCollection, createIndex, and dropCollection.
DDL operations auditing on secondaries has changes. See Audit Events and Filter.
Capped Collections
Capped Collection Deletes Are Replicated to Secondaries
Starting in MongoDB 5.0, the implicit delete operations for replica set capped collections are processed by the primary and replicated to the secondary members.
Explicit Deletes Allowed on Capped Collections
Starting in MongoDB 5.0.7, you can delete documents from capped collections using delete methods.
Change Streams
Change Events Output
Starting in MongoDB 5.0, Change Events
contain the field updateDescription.truncatedArrays
to record array
truncations.
Indexes
Partial Indexes Behavior Change
Starting in MongoDB 5.0, multiple partial indexes can be created using the same key pattern as long as the partialFilterExpression fields do not express equivalent filters.
In earlier versions of MongoDB, creating multiple partial indexes is not allowed when using the same key pattern with different partialFilterExpressions.
Unique Sparse Index Behavior Change
Starting in MongoDB 5.0, unique sparse and unique non-sparse indexes with the same key pattern can exist on a single collection.
Cannot Drop Ready
Indexes During In-Progress Index Builds
The db.collection.dropIndexes()
command cannot drop
ready indexes
if there are any in-progress index builds.
In versions 4.4.0-4.4.4 of MongoDB, this logic was not true due to a bug.
Foreground Validation May Fix Multikey Metadata Inconsistencies
When run on a MongoDB deployment,
db.collection.validate()
attempts to fix
multikey metadata inconsistencies
of standalone deployments.
Removal of geoHaystack
Index and the geoSearch
Command
MongoDB 5.0 removes the deprecated geoHaystack
index and
geoSearch
command. Use a 2d index with
$geoNear
or one of the supported geospatial query
operators instead.
Upgrading your MongoDB instance to 5.0 and setting
featureCompatibilityVersion to 5.0
will delete any
pre-existing geoHaystack
indexes.
New Error Messages
The db.collection.createIndex()
and db.collection.createIndexes()
operations have new error messages when options are specified incorrectly.
Interrupted Index Builds
If a node in a replica set is cleanly shutdown or rolls back during an index build, the index build progress is now saved to disk. When the server restarts, index creation resumes from the saved position.
reIndex
Behavior Change
Starting in MongoDB 5.0, the reIndex
command and the
db.collection.reIndex()
shell method may only be run on
standalone instances.
Removed Commands
Starting in MongoDB 5.0, these database commands and
mongo
shell helper methods are removed:
Removed Command | Alternative |
---|---|
Not available | |
Not available | |
Not available | |
|
Replica Sets
Non-transactional Reads on config.transactions
Starting in MongoDB 5.0, non-transaction reads are not allowed on
the config.transactions
collection with the following
read concerns and options:
"majority"
and the afterClusterTime option is setWhen using a MongoDB Driver and
"majority"
within a causally consistent session
hello
Command
Starting in MongoDB 5.0, the
hello
command and the db.hello()
method were
introduced as replacements for the isMaster
command
and the db.isMaster()
method. The new topology metric
connections.exhaustHello
tracks this in
connections
.
Quiesce Period
Starting in MongoDB 5.0, mongod
and mongos
enter a quiesce period to allow any
ongoing database operations to complete before shutting down.
Limit Removed for members[n]._id
Values
Starting in MongoDB 5.0, the members[n]._id
field may be any
integer value greater than or equal to 0
. Previously, this value was
limited to an integer between 0
and 255
inclusive.
enableMajorityReadConcern
Is Not Configurable
Starting in MongoDB 5.0,
enableMajorityReadConcern
and
--enableMajorityReadConcern
cannot be changed
and are always set to true
due to storage engine improvements.
In earlier versions of MongoDB,
enableMajorityReadConcern
and
--enableMajorityReadConcern
are configurable and can be set
to false
to prevent storage cache pressure from immobilizing a
deployment with a three-member primary-secondary-arbiter (PSA)
architecture.
If you are using a three-member primary-secondary-arbiter (PSA) architecture, consider the following:
The write concern
"majority"
can cause performance issues if a secondary is unavailable or lagging. For advice on how to mitigate these issues, see Mitigate Performance Issues with a Self-Managed PSA Replica Set.If you are using a global default
"majority"
and the write concern is less than the size of the majority, your queries may return stale (not fully replicated) data.
Enhanced Thread Pool Timeout Control
Starting in MongoDB 5.0, you can use the new
replWriterMinThreadCount
server parameter to
allow idle threads above this minimum to be closed.
When replWriterMinThreadCount
is
configured with a value less than replWriterThreadCount
,
idle threads above replWriterMinThreadCount
are timed out.
Reconfiguring PSA Replica Sets
When reconfiguring primary-secondary-arbiter (PSA) replica sets or
changing to a PSA architecture, it is now in some cases required to
perform the reconfiguration in a two-step change. MongoDB 5.0 introduces
the rs.reconfigForPSASet()
method which performs both steps.
If you cannot use the helper method, follow the procedure in
Modify a Self-Managed PSA Replica Set Safely.
Limit Sync Source Re-evaluations
maxNumSyncSourceChangesPerHour
determines how many sync
source changes can happen per hour before the node temporarily stops
re-evaluating a sync source. This parameter will not prevent a node
from starting to sync from another node if it doesn't have a sync
source.
enableOverrideClusterChainingSetting
Server Parameter
Starting in MongoDB 5.0.2, you can set the new
enableOverrideClusterChainingSetting
server parameter to
true
to allow secondary members to replicate data from other
secondary members even if settings.chainingAllowed
is
false
.
Security
Support for Online Certificate Rotation
Starting in MongoDB 5.0, you may now rotate the following TLS
certificates on demand without first needing to stop your running
mongod
or mongos
instance:
CRL (Certificate Revocation List) files
(on Linux and Windows platforms)
To rotate these certificates, replace the certificate files on your
filesystem with updated versions, then use the
rotateCertificates
command or the
db.rotateCertificates()
shell method to trigger certificate
rotation.
Rotating certificates in this manner does not require downtime, and does not drop any active remote connections.
See Online Certificate Rotation for full details.
Support for Configuring TLS 1.3 Cipher Suites
MongoDB 5.0 introduces the opensslCipherSuiteConfig
parameter to enable configuration of the supported cipher suites OpenSSL
should permit when using TLS 1.3 encryption.
TLS Connection X509 Certificate Startup Warning
Starting in MongoDB 5.0, mongod
and mongos
now
issue a startup warning when their certificates do not include a
Subject Alternative Name attribute.
The following platforms do not support common name validation:
iOS 13 and higher
MacOS 10.15 and higher
Go 1.15 and higher
Clients using these platforms will not authenticate to MongoDB servers that use x.509 certificates whose hostnames are specified by CommonName attributes.
ApplyOps Privilege Action
MongoDB 5.0 introduces the applyOps
privilege action which is inherited by dbAdminAnyDatabase
.
The applyOps
action permits users to run the
applyOps
database command.
Sharded Clusters
Resharding
The ideal shard key allows MongoDB to distribute documents evenly
throughout the cluster while facilitating common query patterns. A
suboptimal shard key can lead to performance or scaling issues due to
uneven data distribution. Starting in MongoDB 5.0, you can use the
reshardCollection
command to change the shard key for a collection to change the distribution of
your data across your cluster.
currentOp
Reports Ongoing Resharding Operations
Starting in MongoDB 5.0, the $currentOp
aggregation stage
(and the currentOp
command and db.currentOp()
shell method) include additional information about the status of ongoing
resharding operations for the resharding coordinator and the
donor and recipient shards.
db.currentOp
Method Now Uses Aggregation Stage in mongosh
Starting in MongoDB 5.0, the $currentOp
aggregation
stage is used when running the helper method db.currentOp()
with mongosh
.
mongos
/ mongod
Connection Pool
Starting in MongoDB 5.0,
MongoDB adds the parameter option "automatic"
as the new default for
the ShardingTaskExecutorPoolReplicaSetMatching
. When set
for a mongos
, the instance follows the behavior specified
for the "matchPrimaryNode"
option. When set for a
mongod
, the instance follows the behavior specified for
the "disabled"
option.
renameCollection
Compatible with Sharded Collections
Starting in MongoDB 5.0, you can use the renameCollection
command to change the name of a sharded collection.
When renaming a sharded or unsharded collection in a sharded cluster, the source and target collections are exclusively locked on every shard. Subsequent operations on the source and target collections must wait until the rename operation completes.
movePrimary
Error Message For Writes During Operation
Starting in MongoDB 5.0, when using the movePrimary
command
to remove a shard from a sharded cluster,
writes to the original shard will generate an error message.
Split and Merge Chunk Changelogs Show Owning Shard
Starting in MongoDB 5.0, documents in the config.changelog
collection for
split and
merge operations
contain an owningShard
field. The owningShard
field shows the
shardId
of the shard that owns the chunks that were split or
merged.
The owningShard
field helps identify shards where split or merge
operations frequently occur.
maxCatchUpPercentageBeforeBlockingWrites
Server Parameter
Starting in MongoDB 5.0, you can set the
maxCatchUpPercentageBeforeBlockingWrites
to specify the
maximum allowed percentage of data not yet migrated
during a moveChunk
operation when compared to the
total size (in MBs) of the chunk being transferred.
This parameter can affect the behavior of:
moveChunk
commands that are run manually.Load balancer functionality, which automatically runs multiple
moveChunk
commands to evenly distribute chunks across shards. See Sharded Cluster Balancer.
Shell Changes
New MongoDB Shell: mongosh
The mongo
shell has been deprecated in MongoDB v5.0. The
replacement shell is mongosh
. The legacy mongo
shell
will be removed in a future release.
Shell packaging also changes in MongoDB v5.0. Refer to the installation instructions for further details.
Shell Support for GCP and Azure KMS Providers
Starting in MongoDB 5.0, the Google Cloud Platform KMS and Azure Key Vault
are supported in both mongosh
and the legacy mongo
shell as
Key Management Service (KMS)
providers for Client-Side Field Level Encryption.
Using a KMS, you can centrally and securely store Customer Master Keys (CMKs), which are used to encrypt and decrypt data encryption keys as part of the client-side field level encryption workflow.
In addition, a configured KMS allows for the use of How CSFLE Decrypts Documents of data fields when used with MongoDB Enterprise.
To learn more, see Configure a KMS provider using mongosh.
Snapshots
Extended Support for Read Concern "snapshot"
Starting in MongoDB 5.0, read concern "snapshot"
is
supported for some read operations outside of multi-document
transactions on primaries and secondaries. See
Perform Long-Running Snapshot Queries.
minSnapshotHistoryWindowInSeconds
Server Parameter
Starting in MongoDB 5.0, you can use the
minSnapshotHistoryWindowInSeconds
parameter to control how
long WiredTiger keeps the snapshot history.
Transactions
coordinateCommitReturnImmediatelyAfterPersistingDecision
Parameter
The server parameter
coordinateCommitReturnImmediatelyAfterPersistingDecision
controls when transaction commit decisions are returned to the client.
The parameter was introduced in MongDB 5.0 with a default value of
true
. In MongoDB 6.1 the default value changes to false
.
When coordinateCommitReturnImmediatelyAfterPersistingDecision
is
false
, the shard transaction coordinator
waits for all members to acknowledge a multi-document transaction commit before returning the commit decision to
the client.
Naming Changes
Starting in February 2022, the "Versioned API" terminology was changed to "Stable API". All concepts and features remain the same with this naming change.
General Changes
Execution Plan Statistics for Query with $lookup
Pipeline Stage
MongoDB 5.0 adds execution plan statistics for queries that use a $lookup
pipeline stage.
Improved Handling of ($
) and (.
) in Field Names
MongoDB 5.0 adds improved support for field names that are
($
) prefixed or that contain (.
) characters. The validation
rules for storing data have been updated to make it easier to work with
data sources that use these characters.
Cluster Wide Default Write Concern
Starting in MongoDB 5.0, once the Cluster Wide Write Concern (CWWC)
is set via the setDefaultRWConcern
command the write
concern cannot be unset.
Implicit Default Write Concern
Starting in MongoDB 5.0, the implicit default
write concern is
w: majority
. However, special
considerations are made for deployments containing
arbiters:
The voting majority of a replica set is 1 plus half the number of voting members, rounded down. If the number of data-bearing voting members is not greater than the voting majority, the default write concern is
{ w: 1 }
.In all other scenarios, the default write concern is
{ w: "majority" }
.
Specifically, MongoDB uses the following formula to determine the default write concern:
if [ (#arbiters > 0) AND (#non-arbiters <= majority(#voting-nodes)) ] defaultWriteConcern = { w: 1 } else defaultWriteConcern = { w: "majority" }
For example, consider the following deployments and their respective default write concerns:
Non-Arbiters | Arbiters | Voting Nodes | Majority of Voting Nodes | Implicit Default Write Concern |
---|---|---|---|---|
2 | 1 | 3 | 2 |
|
4 | 1 | 5 | 3 |
|
In the first example:
There are 2 non-arbiters and 1 arbiter for a total of 3 voting nodes.
The majority of voting nodes (1 plus half of 3, rounded down) is 2.
The number of non-arbiters (2) is equal to the majority of voting nodes (2), resulting in an implicit write concern of
{ w: 1 }
.
In the second example:
There are 4 non-arbiters and 1 arbiter for a total of 5 voting nodes.
The majority of voting nodes (1 plus half of 5, rounded down) is 3.
The number of non-arbiters (4) is greater than the majority of voting nodes (3), resulting in an implicit write concern of
{ w: "majority" }
.
The { w: "majority" }
default
write concern provides a stronger
durability guarantee in the event of an election, or if replica set
members become unavailable.
mongosShutdownTimeoutMillisForSignaledShutdown
Parameter
Starting in MongoDB 5.0, the new parameter
mongosShutdownTimeoutMillisForSignaledShutdown
specifies
the time in milliseconds to wait for any ongoing database operations to
complete before initiating a shutdown of mongos
.
Configurable zstd
Compression Level
MongoDB 5.0 introduces the
zstdCompressionLevel
configuration file option which allows for configurable compression
levels when
blockCompressor
is set
to zstd
.
Lock-Free Read Operations
Starting in MongoDB 5.0, the following read operations are not blocked when another operation holds an exclusive (X) write lock on the collection:
When writing to a collection, mapReduce
and
aggregate
hold an intent exclusive (IX) lock. Therefore, if
an exclusive X lock is already held on a collection,
mapReduce
and aggregate
write operations are
blocked.
Schema Validation Failures Explained
MongoDB 5.0 adds detailed explanations when a document fails schema validation.
Repair Option in validate
Command
Starting in MongoDB 5.0, the validate
command and
db.collection.validate()
helper method have a new repair option for repairing a collection that has
inconsistencies.
The validate
command and db.collection.validate()
helper method also return a new repaired
boolean value
that is true
if the collection was repaired.
validate
Command Reports Document Schema Violations
Starting in MongoDB 5.0, validate
and
db.collection.validate()
validates documents
in a collection. The commands report if any
schema validation rules are
violated.
Repair Option in mongod
Starting in MongoDB 5.0, the --repair
option
for mongod
validates the collections to find any
inconsistencies and fixes them if possible, which avoids rebuilding the
indexes. See the --repair
option for usage
and limitations.
corruptRecords
Field in Validation Output
Starting in MongoDB 5.0, the validate
command and
db.collection.validate()
helper method return a new
corruptRecords
field that contains an array of
RecordId
values for corrupt documents.
maxValidateMemoryUsageMB
Server Parameter
Starting in MongoDB 5.0, the setParameter
command has a new maxValidateMemoryUsageMB
parameter, which
sets the maximum memory usage for the validate
command.
findChunksOnConfigTimeoutMS
Server Parameter
Starting in MongoDB 5.0, you can use the
findChunksOnConfigTimeoutMS
parameter to change the timeout
for find operations on chunks
.
Database Profiler filter
Option
Starting in MongoDB 5.0, you can set a filter
option for the
database profiler to determine which
operations are profiled and logged. You can use the filter
expression in place of the slowms
and sampleRate
profiler
options.
See:
Log Changes to Database Profiler Settings
Starting in MongoDB 5.0, changes made to the database profiler level
, slowms
, sampleRate
, or
filter
using the profile
command or
db.setProfilingLevel()
wrapper method are recorded in the
log file
.
Independent Log Rotation for Server and Audit Logs
Starting in MongoDB 5.0, when auditing is
enabled, you may now rotate the server and audit logs
independently using the logRotate
command.
Previously, logRotate
would rotate the two logs together.
remote
Field in Slow Operation Logs
Starting in MongoDB 5.0, slow operation log messages include a
remote
field specifying client IP address.
remoteOpWaitMillis
Log Field
Starting in MongoDB 5.0, you can use the remoteOpWaitMillis log field to obtain the wait time for results from shards.
resolvedViews
Log Field for Slow Queries on Views
Starting in MongoDB 5.0, log messages for slow queries on views
include a resolvedViews
field that contains the view details.
Define Variables Using the let
Option
Starting in MongoDB 5.0, the following commands have a let
option to
define a list of variables. This allows you to improve command
readability by separating the variables from the query text.
find
commandfindAndModify
command and correspondingdb.collection.findAndModify()
shell helperupdate
command and correspondingdb.collection.update()
shell helperdelete
commanddb.collection.remove()
shell helper
The update
command also has a c
field to define a list
of variables.
Support for Username to LDAP DN Mapping by Default
Starting in MongoDB 5.0, the userToDNMapping
configuration file option and the --ldapUserToDNMapping
command line option for
mongod
/ mongos
and mongoldap
now map the authenticated username as the LDAP DN by default if an
empty mapping document (i.e. an empty string or empty array) is
specified to the option. Previously, providing an empty mapping document
would cause mapping to fail.
Additional dbStats
Free Space Statistics
Starting in MongoDB 5.0, the dbStats
command outputs these
additional statistics:
Free space allocated to collections (
freeStorageSize
)Free space allocated to indexes (
indexFreeStorageSize
)Total free space allocated to collections and indexes (
totalFreeStorageSize
)
serverStatus
Output Change
serverStatus
includes the following new fields in its
output:
- Aggregation Metrics
- API Version Metrics
- Replication Metrics
- Read Concern Counters
readConcernCounters
, which reports on the read concern level specified by query operations (readConcernCounters
replacesopReadConcernCounters
)readConcernCounters
now has the following new fields:readConcernCounters.nonTransactionOps.noneInfo
readConcernCounters.transactionOps.noneInfo
- Write Concern Counters
opWriteConcernCounters
now has the following new fields:opWriteConcernCounters.insert.noneInfo
opWriteConcernCounters.update.noneInfo
opWriteConcernCounters.delete.noneInfo
- Number of Threaded Connections
connections.threaded
, which reports the number of incoming connections from clients that are assigned to threads that service client requests
- Resharding Statistics
shardingStatistics.resharding
, which reports statistics about resharding operations
- Service Executor Metrics
network.serviceExecutors
, which reports on the service executors that run operations for client requests
- Cursor Metrics
metrics.cursor.moreThanOneBatch
, which reports the total number of cursors that have returned more than one batch (additional batches are retrieved using thegetMore
command)metrics.cursor.totalOpened
, which reports the total number of cursors that have been opened
- Security Counter
security.authentication.saslSupportedMechsReceived
, which reports the number of times ahello
request includes a validhello.saslSupportedMechs
field.
- Repl
repl
now includes aprimaryOnlyServices
document that contains additional information about services that only run on replica set primaries.
Plan Cache Debug Info Size Limit
Starting in MongoDB 5.0, the
plan cache will save full plan cache
entries only if the cumulative size of the plan caches
for all
collections is lower than 0.5 GB. When the cumulative size of the
plan caches
for all collections exceeds this threshold, additional
plan cache
entries are stored without certain debug information.
The estimated size in bytes of a plan cache
entry is available in
the output of $planCacheStats
.
Closure of Inactive Cursors Opened Within a Session
Starting in MongoDB 5.0, cursors created within a
client session close
when the corresponding server session
ends with the killSessions
command, if the session times
out, or if the client has exhausted the cursor.
See Iterate a Cursor in mongosh
.
New validateDBMetadata
Command
MongoDB 5.0 adds the validateDBMetadata
command. The
validateDBMetadata
command checks that the stored metadata
of a database or a collection is valid within a particular API version.
Performance Considerations
Implicit Default Write Concern
MongoDB 5.0 changes the default write concern to
{ w: "majority" }
. The new default write concern
might impact performance since MongoDB acknowledges writes only after a
calculated majority of replica set
members have executed and persisted the write to disk.
If your application relies on performance-sensitive writes, you can override the default write concern at the cost of data durability guarantees. To override this setting, you can:
Set the write concern at the individual operation level for performance-critical writes. For more information, see your driver documentation.
Use the
setDefaultRWConcern
command to explicitly set the default write concern.
Warning
If write operations use { w: 1 }
write concern,
the rollback directory may exclude writes submitted after an
oplog hole if the primary restarts before the write operation
completes.
local
Default Read Concern
Starting in MongoDB 5.0, "local"
is the default read
concern level for read operations against the primary and secondaries.
This may introduce a significant latency increase for count queries that use a filter and for covered queries.
You can opt out of this behavior by setting the cluster-wide
read concern with
setDefaultRWConcern
.
Snapshot History Retention
MongoDB 5.0 increases the default value of
minSnapshotHistoryWindowInSeconds
to 300
, which might
negatively impact performance. If you aren't using read concern
"snapshot"
, you can reduce the value of the
minSnapshotHistoryWindowInSeconds
parameter to 5
on all
mongod
instances. For more information, see
Snapshot History Retention.
Note
If you are running a sharded cluster, do not change
minSnapshotHistoryWindowInSeconds
on config servers.
Platform Support
Minimum Microarchitecture
MongoDB 5.0 introduces the following minimum microarchitecture requirements:
CPU | Minimum Supported Microarchitecture |
---|---|
Intel | MongoDB 5.0 requires one of:
|
AMD | MongoDB 5.0 requires AMD Bulldozer or later. |
ARM | MongoDB 5.0 requires ARMv8.2-A or later. |
MongoDB v5.0 is not supported on x86_64
or arm64
platforms that
do not meet these minimum microarchitecture requirements.
See x86_64 Platform Support for more information.
Removed Platforms
MongoDB 5.0 removes support for the following platforms:
See Platform Support for the full list of platforms and architectures supported in MongoDB 5.0.
Changes Affecting Compatibility
Some changes can affect compatibility and may require user actions. For a detailed list of compatibility changes, see Compatibility Changes in MongoDB 5.0.
Upgrade Procedures
Important
Feature Compatibility Version
To upgrade to MongoDB 5.0 from a 4.4 deployment, the 4.4 deployment
must have featureCompatibilityVersion
set to 4.4
. To check
the version:
db.adminCommand( { getParameter: 1, featureCompatibilityVersion: 1 } )
To upgrade to MongoDB 5.0, refer to the upgrade instructions specific to your MongoDB deployment:
If you need guidance on upgrading to 5.0, MongoDB professional services offer major version upgrade support to help ensure a smooth transition without interruption to your MongoDB application.
Downgrade Consideration
MongoDB only supports single-version downgrades. You cannot downgrade to a release that is multiple versions behind your current release.
For example, you may downgrade a 5.0-series to a 4.4-series deployment. However, further downgrading that 4.4-series deployment to a 4.2-series deployment is not supported.
Download
To download MongoDB 5.0, go to the MongoDB Download Center.
Known Issues
In Version | Issues | Status |
---|---|---|
5.0.0 | SERVER-58171: A Time Series collection's | Fixed in 5.0.1 |
5.0.0 | SERVER-58392: An ongoing resharding operation may prevent a backup or restore operation from succeeding. | Fixed in 5.0.3 |
Report an Issue
To report an issue, see the MongoDB GitHub repository for instructions on how to file a JIRA ticket for the MongoDB server or one of the related projects.