Error
Error Code:
134
MongoDB Error 134: Read Concern Majority Unavailable
Description
This error signifies that MongoDB cannot fulfill a read operation with `readConcern: "majority"` because the replica set is unable to establish a definitive 'majority' state. This often occurs during replica set initialization, elections, or when a sufficient number of members are unavailable or unsynchronized.
Error Message
Read Concern Majority Not Available Yet
Known Causes
4 known causesReplica Set Instability
The replica set is undergoing an election, reconfiguring, or has not yet reached a stable state with a clear majority of its members online and synchronized.
No Primary Elected
There is currently no primary node available in the replica set to accept write operations and coordinate the majority commit point, preventing majority reads.
Insufficient Data-Bearing Members
A sufficient number of data-bearing replica set members are unavailable (e.g., crashed, unreachable), making it impossible to establish a 'majority' for read concern.
Network Partition or Connectivity Issues
Network problems are preventing replica set members from communicating effectively, leading to a split-brain scenario or an inability to form a consensus majority.
Solutions
4 solutions available1. Allow Time for Majority to Elect easy
Wait for the replica set to stabilize and elect a primary.
1
Monitor the replica set status. This error often occurs during initial setup or after a failover when the replica set has not yet established a stable primary and a majority of secondaries have caught up.
rs.status()2
Wait for a period of time. The exact duration depends on network latency, disk I/O, and the amount of data being replicated. For small deployments, this might be a few minutes. For larger ones, it could be longer.
text3
Re-attempt the operation that triggered the error. Once a primary is elected and a majority of secondaries are in sync, read concern majority should become available.
text2. Adjust Read Concern for the Operation easy
Temporarily use a lower read concern level for specific operations.
1
Identify the operation that is failing due to the 'Read Concern Majority Not Available Yet' error. This could be a find, aggregate, or other read operation.
text2
Modify the read concern level for that specific operation. Instead of 'majority', use 'local' or 'available'. Note that 'local' reads from the current node, and 'available' reads from any node that can serve the read.
db.collection.find( { query }, { readConcern: { level: 'local' } } )3
If the issue persists with 'local', consider 'available' as a fallback, but understand the potential consistency implications.
db.collection.find( { query }, { readConcern: { level: 'available' } } )4
Once the replica set stabilizes and read concern majority becomes available, revert the read concern level to 'majority' for guaranteed consistency.
text3. Verify Replica Set Configuration and Health medium
Ensure the replica set is properly configured and all members are healthy.
1
Connect to your MongoDB instance and run `rs.status()` to examine the replica set's health.
rs.status()2
Check for any members in an unhealthy state (e.g., `STARTUP`, `STARTUP2`, `RECOVERING`, `ROLLBACK`, `UNHEALTHY`). Address any issues reported for individual members.
text3
Ensure that the `settings.electionTimeoutMillis` and `settings.heartbeatIntervalMillis` in your replica set configuration are appropriate for your network environment. These values can affect how quickly elections occur and how members detect failures.
db.adminCommand( { replSetGetConfig: 1 } )4
Verify that all replica set members have consistent `protocolVersion` and `pv` values.
text5
If network latency is high between members, consider tuning these parameters or improving network connectivity. High latency can delay elections and replication, leading to this error.
text4. Force an Election (Use with Caution) advanced
Manually trigger an election if the replica set is stuck.
1
Connect to a secondary member of the replica set that is not the current primary.
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Execute the `replSetStepDown` command. This will cause the current primary to step down, initiating an election process. You can specify a `seconds` parameter to control how long the primary remains stepped down.
db.adminCommand( { replSetStepDown: 60 } )3
Monitor `rs.status()` to observe the election process and confirm a new primary is elected.
rs.status()4
Once a new primary is elected and the replica set has stabilized, re-attempt the operation that caused the error.
text5
This is a disruptive operation and should be used cautiously in production environments as it can temporarily impact availability.
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