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2.6 Changelog 
 
2.6.12 Changelog 
Security 
SERVER-19284  Should not be able to create role with same name as builtin role
 
Sharding 
SERVER-17886  dbKillCursors op asserts on mongos when at log level 3 
SERVER-19266  An error document is returned with result set 
SERVER-20191  multi-updates/remove can make successive queries skip shard version checking 
SERVER-20839  trace_missing_docs_test.js compares Timestamp instances using < operator in mongo shell 
 
Query 
SERVER-2454  Queries that are killed during a yield should return error to user instead of partial result set 
SERVER-16042  Optimise $all/$and to select smallest subset as initial index bounds 
SERVER-19725  NULL pointer crash in QueryPlanner::plan with $near operator 
SERVER-20083  Add log statement at default log level for when an index filter is set or cleared successfully 
SERVER-20829  RUNNER_DEAD on document delete during update by _id or find by _id 
SERVER-21227  MultiPlanStage::invalidate() should not flag and drop invalidated WorkingSetMembers 
SERVER-21602  Reduce execution time of cursor_timeout.js 
SERVER-22195  queryoptimizer3.js failing on 2.6 
SERVER-22535  Some index operations (drop index, abort index build, update TTL config) on collection during active migration can cause migration to skip documents 
 
Write Operations 
SERVER-21647  $rename changes field ordering
 
Storage 
SERVER-21543  Lengthen delay before deleting old journal files
MMAP 
SERVER-22261  MMAPv1 LSNFile may be updated ahead of what is synced to data files 
 
 
Build and Packaging 
SERVER-18432  alert when passing unused variables to scons 
SERVER-18793  Enterprise RPM build issues 
SERVER-19509  The nproc ulimits are different across packages 
SERVER-20583  migrate all windows-64 vs2010 builders in evergreen to use new version of the distribution 
SERVER-20830  set push and docs_tickets tasks as not available for patch testing 
SERVER-21864  streamline artifact signing procedure to support coherent release process 
 
 
 
2.6.11 -- Changes 
Querying 
SERVER-19553   mongod  shouldn't use sayPiggyBack to send killCursor messages 
SERVER-18620  Reduce frequency of "staticYield can't unlock" log message 
SERVER-18461  Range predicates comparing against a BinData value should be covered, but are not in 2.6 
SERVER-17815  Plan ranking tie breaker is computed incorrectly 
SERVER-16265  Add query details to getmore entry in profiler and db.currentOp() 
SERVER-15217  v2.6 query plan ranking test "NonCoveredIxisectFetchesLess" relies on order of deleted record list 
SERVER-14070  Compound index not providing sort if equality predicate given on sort field 
 
Sharding 
SERVER-19464   $sort  stage in aggregation doesn't call scoped connections done () 
SERVER-18955   mongos  doesn't set batch size (and keeps the old one, 0) on getMore if performed on first _cursor->more() 
 
Indexing 
SERVER-19559  Document growth of "key too large" document makes it disappear from the index 
SERVER-16348  Assertion failure n >= 0 && n < static_cast<int>(_files.size()) src/mongo/db/storage/extent_manager.cpp 109 
SERVER-13875   ensureIndex()  of 2dsphere index breaks after upgrading to 2.6 (with the new createIndex command) 
 
Build and Testing 
SERVER-18097  Remove mongosTest_auth and mongosTest_WT tasks from evergreen.yml 
SERVER-18068  Coverity analysis defect 72413: Resource leak 
SERVER-18371  Add SSL library config detection 
 
 
2.6.10 -- Changes 
Security 
SERVER-18312  Upgrade PCRE to latest 
SERVER-17812  LockPinger has audit-related GLE failure 
SERVER-17647  Compute BinData length in v8 
SERVER-17591  Add SSL flag to select supported protocols 
SERVER-16849  On mongos we always invalidate the user cache once, even if no user definitions are changing 
SERVER-11980  Improve user cache invalidation enforcement on mongos 
 
Querying 
SERVER-18364  Ensure non-negation predicates get chosen over negation predicates for multikey index bounds construction 
SERVER-17815  Plan ranking tie breaker is computed incorrectly 
SERVER-16256  $all clause with elemMatch uses wider bounds than needed 
 
Replication 
SERVER-18211  MongoDB fails to correctly roll back collection creation 
SERVER-17771  Reconfiguring a replica set to remove a node causes a segmentation fault on 2.6.8 
SERVER-13542  Expose electionId on primary in isMaster 
 
Storage 
SERVER-18211  MongoDB fails to correctly roll back collection creation 
SERVER-17653  ERROR: socket XXX is higher than 1023; not supported on 2.6.* 
 
Indexing 
SERVER-17018  Assertion failure false src/mongo/db/structure/btree/key.cpp Line 433 on remove operation
 
Networking 
SERVER-18096  Shard primary incorrectly reuses closed sockets after relinquish and re-election 
SERVER-17591  Add SSL flag to select supported protocols 
 
Build and Packaging 
SERVER-18344  logs should be sent to updated logkeeper server 
SERVER-18082  Change smoke.py buildlogger command line options to environment variables 
SERVER-18312  Upgrade PCRE to latest 
SERVER-17780  Init script sets process ulimit to different value compared to documentation 
SERVER-16563  Debian repo component mismatch - mongodb/10gen 
 
Shell 
SERVER-17951  db.currentOp() fails with read preference set
 
Testing 
SERVER-18262  setup_multiversion_mongodb should retry links download on timeouts 
SERVER-18229  smoke.py with PyMongo 3.0.1 fails to run certain tests 
SERVER-18073  Fix smoke.py to work with PyMongo 3.0 
 
 
2.6.9 -- Changes 
Security 
SERVER-16073  Create hidden net.ssl.sslCipherConfig flag
 
Querying 
SERVER-14723  Crash during query planning for geoNear command with multiple 2dsphere indexes 
SERVER-14071  For queries with sort() , bad non-blocking plan can be cached if there are zero results 
SERVER-8188  Configurable idle cursor timeout 
 
Replication and Sharding 
SERVER-17429  the message logged when changing sync target due to stale data should format OpTimes in a consistent way 
SERVER-17441   mongos  crash right after "not master" error 
 
Storage 
SERVER-15907  Use ftruncate rather than fallocate when running on tmpfs
 
Aggregation Framework 
SERVER-17426  Aggregation framework query by _id returns duplicates in sharded cluster (orphan documents) 
SERVER-17224  Aggregation pipeline with 64MB document can terminate server 
 
Diagnostics and Internal Code 
SERVER-17226   top  command with 64MB result document can terminate server 
SERVER-17338  NULL pointer crash when running copydb against stepped-down 2.6 primary 
SERVER-14992  Query for Windows 7 File Allocation Fix, and other hotfixes 
 
 
2.6.8 -- Changes 
Query and Aggregation 
SERVER-16655  Geo predicate is unable to use compound 2dsphere index if it is root of $or  clause 
SERVER-16527  2dsphere explain reports "works" for nscanned & nscannedObjects 
SERVER-15802  Query optimizer should always use equality predicate over unique index when possible 
SERVER-14044  Incorrect {$meta: 'text'} reference in aggregation $sort  error message 
 
Replication 
SERVER-16599  copydb and clone commands can crash the server if a primary steps down 
SERVER-16315  Replica set nodes should not threaten to veto nodes whose config version is higher than their own 
SERVER-16274  secondary fasserts trying to replicate an index 
SERVER-15471  Better error message when replica is not found in GhostSync::associateSlave 
 
Sharding 
SERVER-17191  Spurious warning during upgrade of sharded cluster 
SERVER-17163  Fatal error "logOp but not primary" in MigrateStatus::go 
SERVER-16984  UpdateLifecycleImpl can return empty collectionMetadata even if ns is sharded 
SERVER-10904  Possible for _master and _slaveConn to be pointing to different connections even with primary read pref 
 
Storage 
SERVER-17087  Add listCollections command functionality to 2.6 shell & client 
SERVER-14572  Increase C runtime stdio file limit 
 
Build and Packaging 
SERVER-14803  Support static libstdc++ builds for non-Linux builds 
SERVER-15400  Create Windows Enterprise Zip File with vcredist and dependent dlls 
 
Usability 
SERVER-14756  The YAML storage.quota.enforced option is not found
 
Testing 
SERVER-16421  sharding_rs2.js should clean up data on all replicas
 
 
2.6.7 -- Changes 
Stability 
SERVER-16237  Don't check the shard version if the primary server is down 
 
Querying 
SERVER-16408  max_time_ms.js should not run in parallel suite. 
 
Replication 
SERVER-16732  SyncSourceFeedback::replHandshake() may perform an illegal erase from a std::map in some circumstances 
 
Sharding 
SERVER-16683  Decrease mongos memory footprint when shards have several tags 
SERVER-15766  prefix_shard_key.js depends on primary allocation to particular shards 
SERVER-14306  mongos  can cause shards to hit the in-memory sort limit by requesting more results than needed. 
 
Packaging 
SERVER-16081  /etc/init.d/mongod startup script fails, with dirname message 
 
 
2.6.6 -- Changes 
Stability 
SERVER-12061  Do not silently ignore read errors when syncing a replica set node 
SERVER-12058  Primary should abort if encountered problems writing to the oplog 
 
Querying 
SERVER-16291  Cannot set/list/clear index filters on the secondary 
SERVER-15958  The "isMultiKey" value is not correct in the output of aggregation explain plan 
SERVER-15899  Querying against path in document containing long array of subdocuments with nested arrays causes stack overflow 
SERVER-15696  $regex , $in  and $sort  with index returns too many results 
SERVER-15639  Text queries can return incorrect results and leak memory when multiple predicates given on same text index prefix field 
SERVER-15580  Evaluating candidate query plans with concurrent writes on same collection may crash mongod 
SERVER-15528  Distinct queries can scan many index keys without yielding read lock 
SERVER-15485  CanonicalQuery::canonicalize can leak a LiteParsedQuery 
SERVER-15403  $min and $max equal errors in 2.6 but not in 2.4 
SERVER-15233  Cannot run planCacheListQueryShapes on a Secondary 
SERVER-14799  count  with hint doesn't work when hint is a document 
 
Replication 
SERVER-16107  2.6 mongod  crashes with segfault when added to a 2.8 replica set with >= 12 nodes. 
SERVER-15994  listIndexes and listCollections can be run on secondaries without slaveOk bit 
SERVER-15849  do not forward replication progress for nodes that are no longer part of a replica set 
SERVER-15491  SyncSourceFeedback can crash due to a SocketException in authenticateInternalUser 
 
Sharding 
SERVER-15318  copydb should not use exhaust flag when used against mongos 
SERVER-14728  Shard depends on string comparison of replica set connection string 
SERVER-14506  special top chunk logic can move max chunk to a shard with incompatible tag 
SERVER-14299  For sharded limit=N queries with sort, mongos can request >N results from shard 
SERVER-14080  Have migration result reported in the changelog correctly 
SERVER-12472  Fail MoveChunk if an index is needed on TO shard and data exists 
 
Storage 
SERVER-16283  Can't start new wiredtiger node with log file or config file in data directory - false detection of old mmapv1 files 
SERVER-15986  Starting with different storage engines in the same dbpath should error/warn 
SERVER-14057  Changing TTL expiration time with collMod does not correctly update index definition 
 
Indexing and write Operations 
SERVER-14287  ensureIndex can abort reIndex and lose indexes 
SERVER-14886  Updates against paths composed with array index notation and positional operator fail with error 
 
Data Aggregation 
SERVER-15552  Errors writing to temporary collections during mapReduce  command execution should be operation-fatal
 
Build and Packaging 
SERVER-14184  Unused preprocessor macros from s2 conflict on OS X Yosemite 
SERVER-14015  S2 Compilation on GCC 4.9/Solaris fails 
SERVER-16017  Suse11 enterprise packages fail due to unmet dependencies 
SERVER-15598  Ubuntu 14.04 Enterprise packages depend on unavailable libsnmp15 package 
SERVER-13595  Red Hat init.d script error: YAML config file parsing 
 
Logging and Diagnostics 
SERVER-13471  Increase log level of "did reduceInMemory" message in map/reduce 
SERVER-16324  Command execution log line displays "query not recording (too large)" instead of abbreviated command object 
SERVER-10069  Improve errorcodes.py so it captures multiline messages 
 
Testing and Internals 
SERVER-15632  MultiHostQueryOp::PendingQueryContext::doBlockingQuery can leak a cursor object 
SERVER-15629  GeoParser::parseMulti{Line|Polygon} does not clear objects owned by out parameter 
SERVER-16316  Remove unsupported behavior in shard3.js 
SERVER-14763  Update jstests/sharding/split_large_key.js 
SERVER-14249  Add tests for querying oplog via mongodump using --dbpath 
SERVER-13726  indexbg_drop.js 
 
 
2.6.5 -- Changes 
Security 
SERVER-15465  OpenSSL crashes on stepdown 
SERVER-15360  User document changes made on a 2.4 primary and replicated to a 2.6 secondary don't make the 2.6 secondary invalidate its user cache 
SERVER-14887  Allow user document changes made on a 2.4 primary to replicate to a 2.6 secondary 
SERVER-14727  Details of SASL failures aren't logged 
SERVER-12551  Audit DML/CRUD operations 
 
Stability 
SERVER-9032  mongod fails when launched with misconfigured locale
 
Querying 
SERVER-15287  Query planner sort analysis incorrectly allows index key pattern plugin fields to provide sort 
SERVER-15286  Assertion in date indexes when opposite-direction-sorted and double "or" filtered 
SERVER-15279  Disable hash-based index intersection (AND_HASH) by default 
SERVER-15152  When evaluating plans, some index candidates cause complete index scan 
SERVER-15015  Assertion failure when combining $max and $min and reverse index scan 
SERVER-15012  Server crashes on indexed rooted $or queries using a 2d index 
SERVER-14969  Dropping index during active aggregation operation can crash server 
SERVER-14961  Plan ranker favors intersection plans if predicate generates empty range index scan 
SERVER-14892  Invalid {$elemMatch: {$where}} query causes memory leak 
SERVER-14706  Queries that use negated $type predicate over a field may return incomplete results when an index is present on that field 
SERVER-13104  Plan enumerator doesn't enumerate all possibilities for a nested $or 
SERVER-14984  Server aborts when running $centerSphere  query with NaN radius 
SERVER-14981  Server aborts when querying against 2dsphere index with coarsestIndexedLevel:0 
SERVER-14831  Text search trips assertion when default language only supported in textIndexVersion=1 used 
 
Replication 
SERVER-15038  Multiple background index builds may not interrupt cleanly for commands, on secondaries 
SERVER-14887  Allow user document changes made on a 2.4 primary to replicate to a 2.6 secondary 
SERVER-14805  Use multithreaded oplog replay during initial sync 
 
Sharding 
SERVER-15056  Sharded connection cleanup on setup error can crash mongos 
SERVER-13702  Commands without optional query may target to wrong shards on mongos 
SERVER-15156  MongoDB upgrade 2.4 to 2.6 check returns error in config.changelog collection 
 
Storage 
SERVER-15369  explicitly zero .ns files on creation 
SERVER-15319  Verify 2.8 freelist is upgrade-downgrade safe with 2.6 
SERVER-15111  partially written journal last section causes recovery to fail 
 
Indexing 
SERVER-14848  Port index_id_desc.js to v2.6 and master branches 
SERVER-14205  ensureIndex failure reports ok: 1 on some failures 
 
Write Operations 
SERVER-15106  Incorrect nscanned and nscannedObjects for idhack updates in 2.6.4 profiler or slow query log 
SERVER-15029  The $rename  modifier uses incorrect dotted source path 
SERVER-14829  UpdateIndexData::clear() should reset all member variables 
 
Data Aggregation 
SERVER-15087  Server crashes when running concurrent mapReduce and dropDatabase commands 
SERVER-14969  Dropping index during active aggregation operation can crash server 
SERVER-14168  Warning logged when incremental MR collections are unsuccessfully dropped on secondaries 
 
Packaging 
SERVER-14679  (CentOS 7/RHEL 7) init.d script should create directory for pid file if it is missing 
SERVER-14023  Support for RHEL 7 Enterprise .rpm packages 
SERVER-13243  Support for Ubuntu 14 "Trusty" Enterprise .deb packages 
SERVER-11077  Support for Debian 7 Enterprise .deb packages 
SERVER-10642  Generate Community and Enterprise packages for SUSE 11 
 
Logging and Diagnostics 
SERVER-14964  nscanned not written to the logs at logLevel 1 unless slowms exceeded or profiling enabled 
SERVER-12551  Audit DML/CRUD operations 
SERVER-14904  Adjust dates in tool/exportimport_date.js to account for different timezones 
 
Internal Code and Testing 
SERVER-13770  Helpers::removeRange should check all runner states 
SERVER-14284  jstests should not leave profiler enabled at test run end 
SERVER-14076  remove test replset_remove_node.js 
SERVER-14778  Hide function and data pointers for natively-injected v8 functions 
 
 
2.6.4 -- Changes 
Security 
SERVER-14701  The "backup" auth role should allow running the "collstats" command for all resources 
SERVER-14518  Allow disabling hostname validation for SSL 
SERVER-14268  Potential information leak 
SERVER-14170  Cannot read from secondary if both audit and auth are enabled in a sharded cluster 
SERVER-13833  userAdminAnyDatabase role should be able to create indexes on admin.system.users and admin.system.roles 
SERVER-12512  Add role-based, selective audit logging. 
SERVER-9482  Add build flag for sslFIPSMode 
 
Querying 
SERVER-14625  Query planner can construct incorrect bounds for negations inside $elemMatch 
SERVER-14607  hash intersection of fetched and non-fetched data can discard data from a result 
SERVER-14532  Improve logging in the case of plan ranker ties 
SERVER-14350  Server crash when $centerSphere has non-positive radius 
SERVER-14317  Dead code in IDHackRunner::applyProjection 
SERVER-14311  skipping of index keys is not accounted for in plan ranking by the index scan stage 
SERVER-14123  some operations can create BSON object larger than the 16MB limit 
SERVER-14034  Sorted $in query with large number of elements can't use merge sort 
SERVER-13994  do not aggressively pre-fetch data for parallelCollectionScan 
 
Replication 
SERVER-14665  Build failure for v2.6 in closeall.js caused by access violation reading _me 
SERVER-14505  cannot dropAllIndexes when index builds in progress assertion failure 
SERVER-14494  Dropping collection during active background index build on secondary triggers segfault 
SERVER-13822  Running resync before replset config is loaded can crash mongod 
SERVER-11776  Replication 'isself' check should allow mapped ports 
 
Sharding 
SERVER-14551  Runner yield during migration cleanup (removeRange) results in fassert 
SERVER-14431  Invalid chunk data after splitting on a key that's too large 
SERVER-14261  stepdown during migration range delete can abort mongod 
SERVER-14032  v2.6 mongos  doesn't verify _id is present for config server upserts 
SERVER-13648  better stats from migration cleanup 
SERVER-12750  mongos  shouldn't accept initial query with "exhaust" flag set 
SERVER-9788  mongos  does not re-evaluate read preference once a valid replica set member is chosen 
SERVER-9526  Log messages regarding chunks not very informative when the shard key is of type BinData 
 
Storage 
SERVER-14198  Std::set<pointer> and Windows Heap Allocation Reuse produces non-deterministic results 
SERVER-13975  Creating index on collection named "system" can cause server to abort 
SERVER-13729  Reads & Writes are blocked during data file allocation on Windows 
SERVER-13681  mongod  B stalls during background flush on Windows 
 
Indexing 
SERVER-14494  Dropping collection during active background index build on secondary triggers segfault
 
Write Ops 
SERVER-14257  "remove" command can cause process termination by throwing unhandled exception if profiling is enabled 
SERVER-14024  Update fails when query contains part of a DBRef and results in an insert (upsert:true) 
SERVER-13764  debug mechanisms report incorrect nscanned / nscannedObjects for updates 
 
Networking 
SERVER-13734  Remove catch (...) from handleIncomingMsg
 
Geo 
SERVER-14039  $nearSphere query with 2d index, skip, and limit returns incomplete results 
SERVER-13701  Query using 2d index throws exception when using explain() 
 
Text Search 
SERVER-14738  Updates to documents with text-indexed fields may lead to incorrect entries 
SERVER-14027  Renaming collection within same database fails if wildcard text index present 
 
Packaging 
SERVER-14283  Parameters in installed config file are out of date
 
JavaScript 
SERVER-14254  Do not store native function pointer as a property in function prototype 
SERVER-13798  v8 garbage collection can cause crash due to independent lifetime of DBClient and Cursor objects 
SERVER-13707  mongo shell may crash when converting invalid regular expression 
 
Shell 
SERVER-14341  negative opcounter values in serverStatus 
SERVER-14107  Querying for a document containing a value of either type Javascript or JavascriptWithScope crashes the shell 
 
Usability 
SERVER-13833  userAdminAnyDatabase role should be able to create indexes on admin.system.users and admin.system.roles
 
Testing 
SERVER-14731  plan_cache_ties.js sometimes fails 
SERVER-14147  make index_multi.js retry on connection failure 
SERVER-13615  sharding_rs2.js intermittent failure due to reliance on opcounters 
 
 
2.6.3 -- Changes 
SERVER-14302  Fixed: "Equality queries on _id with projection may return no results on sharded collections" 
SERVER-14304  Fixed: "Equality queries on _id with projection on _id may return orphan documents on sharded collections" 
 
2.6.2 -- Changes 
Querying 
SERVER-13731  Fixed: "Stack overflow when parsing deeply nested $not  query" 
SERVER-13890  Fixed: "Index bounds builder constructs invalid bounds for multiple negations joined by an $or " 
SERVER-13752  Verified assertion on empty $in  clause and sort on second field in a compound index. 
SERVER-13337  Re-enabled idhack for queries with projection. 
SERVER-13715  Fixed: "Aggregation pipeline execution can fail with $or and blocking sorts" 
SERVER-13714  Fixed: "non-top-level indexable $not  triggers query planning bug" 
SERVER-13769  Fixed: "distinct  command on indexed field with geo predicate fails to execute" 
SERVER-13675  Fixed "Plans with differing performance can tie during plan ranking" 
SERVER-13899  Fixed: "'Whole index scan' query solutions can use incompatible indexes, return incorrect results" 
SERVER-13852  Fixed "IndexBounds::endKeyInclusive not initialized by constructor" 
SERVER-14073  planSummary no longer truncated at 255 characters 
SERVER-14174  Fixed: "If ntoreturn is a limit (rather than batch size) extra data gets buffered during plan ranking" 
SERVER-13789  Some nested queries no longer trigger an assertion error 
SERVER-14064  Added planSummary information for count  command log message. 
SERVER-13960  Queries containing $or  no longer miss results if multiple clauses use the same index. 
SERVER-14180  Fixed: "Crash with 'and' clause, $elemMatch , and nested $mod  or regex" 
SERVER-14176  Natural order sort specification no longer ignored if query is specified. 
SERVER-13754  Bounds no longer combined for $or  queries that can use merge sort. 
 
Geospatial 
SERVER-13687  Results of $near  query on compound multi-key 2dsphere index are now sorted by distance.
 
Write Operations 
SERVER-13802  Insert field validation no longer stops at first Timestamp() field.
 
Replication 
SERVER-13993  Fixed: "log a message when shouldChangeSyncTarget() believes a node should change sync targets" 
SERVER-13976  Fixed: "Cloner needs to detect failure to create collection" 
 
Sharding 
SERVER-13616  Resolved: "'type 7' (OID) error when acquiring distributed lock for first time" 
SERVER-13812  Now catches exception thrown by getShardsForQuery for geo query. 
SERVER-14138  mongos  will now correctly target multiple shards for nested field shard key predicates. 
SERVER-11332  Fixed: "Authentication requests delayed if first config server is unresponsive" 
 
Storage 
SERVER-13750  convertToCapped  on empty collection no longer aborts after invariant() failure. 
SERVER-14056  Moving large collection across databases with renameCollection no longer triggers fatal assertion. 
SERVER-14082  Fixed: "Excessive freelist scanning for MaxBucket" 
SERVER-13737  CollectionOptions parser now skips non-numeric for "size"/"max" elements if values non-numeric. 
 
Build and Packaging 
SERVER-13950  MongoDB Enterprise now includes required dependency list. 
SERVER-13862  Support for mongodb-org-server installation 2.6.1-1 on RHEL5 via RPM. 
SERVER-13724  Added SCons flag to override treating all warnings as errors. 
 
Shell 
SERVER-13865  Shell now returns correct WriteResult for compatibility-mode upsert with non-OID equality predicate on _id field. 
SERVER-13037  Fixed typo in error message for "compatibility mode". 
 
Internal Code 
SERVER-13794  Fixed: "Unused snapshot history consuming significant heap space" 
SERVER-13446  Removed Solaris builds dependency on ILLUMOS libc. 
SERVER-14092  MongoDB upgrade 2.4 to 2.6 check no longer returns an error in internal collections. 
SERVER-14000  Added new lsb file location for Debian 7.1 
 
Testing 
SERVER-13723  Stabilized tags.js after a change in its timeout when it was ported to use write commands. 
SERVER-13494  Fixed: "setup_multiversion_mongodb.py doesn't download 2.4.10 because of non-numeric version sorting" 
SERVER-13603  Fixed: "Test suites with options tests fail when run with --nopreallocj" 
SERVER-13948  Fixed: "awaitReplication() failures related to getting a config version from master causing test failures" 
SERVER-13839  Fixed sync2.js failure. 
SERVER-13972  Fixed connections_opened.js failure. 
SERVER-13712  Reduced peak disk usage of test suites. 
SERVER-14249  Added tests for querying oplog via mongodump  using --dbpath 
SERVER-10462  Fixed: "Windows file locking related buildbot failures" 
 
 
2.6.1 -- Changes 
Stability 
SERVER-13739  Repair database failure can delete database files
 
Build and Packaging 
SERVER-13287  Addition of debug symbols has doubled compile time 
SERVER-13563  Upgrading from 2.4.x to 2.6.0 via yum clobbers configuration file 
SERVER-13691  yum and apt "stable" repositories contain release candidate 2.6.1-rc0 packages 
SERVER-13515  Cannot install MongoDB as a service on Windows 
 
Querying 
SERVER-13066  Negations over multikey fields do not use index 
SERVER-13495  Concurrent GETMORE and KILLCURSORS operations can cause race condition and server crash 
SERVER-13503  The $where  operator should not be allowed under $elemMatch 
SERVER-13537  Large skip and and limit values can cause crash in blocking sort stage 
SERVER-13557  Incorrect negation of $elemMatch value in 2.6 
SERVER-13562  Queries that use tailable cursors do not stream results if skip() is applied 
SERVER-13566  Using the OplogReplay flag with extra predicates can yield incorrect results 
SERVER-13611  Missing sort order for compound index leads to unnecessary in-memory sort 
SERVER-13618  Optimization for sorted $in queries not applied to reverse sort order 
SERVER-13661  Increase the maximum allowed depth of query objects 
SERVER-13664  Query with $elemMatch  using a compound multikey index can generate incorrect results 
SERVER-13677  Query planner should traverse through $all while handling $elemMatch object predicates 
SERVER-13766  Dropping index or collection while $or query is yielding triggers fatal assertion 
 
Geospatial 
SERVER-13666  $near  queries with out-of-bounds points in legacy format can lead to crashes 
SERVER-13540  The geoNear command no longer returns distance in radians for legacy point 
SERVER-13486 : The geoNear command can create too large BSON objects for aggregation. 
 
Replication 
SERVER-13500  Changing replica set configuration can crash running members 
SERVER-13589  Background index builds from a 2.6.0 primary fail to complete on 2.4.x secondaries 
SERVER-13620  Replicated data definition commands will fail on secondaries during background index build 
SERVER-13496  Creating index with same name but different spec in mixed version replicaset can abort replication 
 
Sharding 
SERVER-12638  Initial sharding with hashed shard key can result in duplicate split points 
SERVER-13518  The _id field is no longer automatically generated by mongos  when missing 
SERVER-13777  Migrated ranges waiting for deletion do not report cursors still open 
 
Security 
SERVER-9358   Log rotation can overwrite previous log files 
SERVER-13644  Sensitive credentials in startup options are not redacted and may be exposed 
SERVER-13441  Inconsistent error handling in user management shell helpers 
 
Write Operations 
SERVER-13466  Error message in collection creation failure contains incorrect namespace 
SERVER-13499  Yield policy for batch-inserts should be the same as for batch-updates/deletes 
SERVER-13516  Array updates on documents with more than 128 BSON elements may crash mongod