Similar to RUBY-1223, I had the problem in past and it's back again. I'm using MongoDB 4.4.1 in RS, mongo gem 2.13.1 and mongoid 7.1.2.
The mongo logger is spammed with this every 10 seconds:
D, [2020-10-12T15:18:03.840198 #6169] DEBUG -- : MONGODB | Server description for db1.updn.io:27017 changed from 'secondary' to 'secondary'. D, [2020-10-12T15:18:03.840335 #6169] DEBUG -- : MONGODB | There was a change in the members of the 'ReplicaSetWithPrimary' topology. D, [2020-10-12T15:18:06.814294 #6169] DEBUG -- : MONGODB | Server description for db3.updn.io:27017 changed from 'primary' to 'primary'. D, [2020-10-12T15:18:06.814499 #6169] DEBUG -- : MONGODB | There was a change in the members of the 'ReplicaSetWithPrimary' topology. D, [2020-10-12T15:18:07.357489 #6169] DEBUG -- : MONGODB | Server description for db3.updn.io:27017 changed from 'primary' to 'primary' [awaited]. D, [2020-10-12T15:18:07.357692 #6169] DEBUG -- : MONGODB | There was a change in the members of the 'ReplicaSetWithPrimary' topology. D, [2020-10-12T15:18:07.382790 #6169] DEBUG -- : MONGODB | Server description for db2.updn.io:27017 changed from 'secondary' to 'secondary' [awaited]. D, [2020-10-12T15:18:07.382927 #6169] DEBUG -- : MONGODB | There was a change in the members of the 'ReplicaSetWithPrimary' topology. D, [2020-10-12T15:18:07.717933 #6169] DEBUG -- : MONGODB | Server description for db1.updn.io:27017 changed from 'secondary' to 'secondary' [awaited]. D, [2020-10-12T15:18:07.718082 #6169] DEBUG -- : MONGODB | There was a change in the members of the 'ReplicaSetWithPrimary' topology. D, [2020-10-12T15:18:07.748347 #6169] DEBUG -- : MONGODB | Server description for db2.updn.io:27017 changed from 'secondary' to 'secondary'. D, [2020-10-12T15:18:07.748459 #6169] DEBUG -- : MONGODB | There was a change in the members of the 'ReplicaSetWithPrimary' topology. D, [2020-10-12T15:18:13.938602 #6169] DEBUG -- : MONGODB | Server description for db1.updn.io:27017 changed from 'secondary' to 'secondary'. D, [2020-10-12T15:18:13.938721 #6169] DEBUG -- : MONGODB | There was a change in the members of the 'ReplicaSetWithPrimary' topology.
The mongoid config is the following:
production:
clients:
default:
database: updown
hosts:
- db1.updn.io
- db2.updn.io
- db3.updn.io
options:
user: updown
password: <%= Rails.application.credentials.dig(:mongodb, :production) %>
compressors: [zlib]
retry_writes: true
max_read_retries: 3
read:
mode: :primary_preferred
max_pool_size: 100
wait_queue_timeout: 5
socket_timeout: 20
The the RS config is the following:
rs0:PRIMARY> rs.config()
{
"_id" : "rs0",
"version" : 71319,
"protocolVersion" : NumberLong(1),
"writeConcernMajorityJournalDefault" : true,
"members" : [
{
"_id" : 14,
"host" : "db2.updn.io:27017",
"arbiterOnly" : false,
"buildIndexes" : true,
"hidden" : false,
"priority" : 2,
"tags" : {
},
"slaveDelay" : NumberLong(0),
"votes" : 1
},
{
"_id" : 16,
"host" : "db1.updn.io:27017",
"arbiterOnly" : false,
"buildIndexes" : true,
"hidden" : false,
"priority" : 1,
"tags" : {
},
"slaveDelay" : NumberLong(0),
"votes" : 1
},
{
"_id" : 17,
"host" : "db3.updn.io:27017",
"arbiterOnly" : false,
"buildIndexes" : true,
"hidden" : false,
"priority" : 2,
"tags" : {
},
"slaveDelay" : NumberLong(0),
"votes" : 1
}
],
"settings" : {
"chainingAllowed" : true,
"heartbeatIntervalMillis" : 2000,
"heartbeatTimeoutSecs" : 10,
"electionTimeoutMillis" : 30000,
"catchUpTimeoutMillis" : 2000,
"catchUpTakeoverDelayMillis" : 30000,
"getLastErrorModes" : {
},
"getLastErrorDefaults" : {
"w" : 1,
"wtimeout" : 10000
}
}
}
Look like a bug again in the detection of changes in mongo driver (because there's no changes) but if there's anything I'm doing wrong please let me know 
- related to
-
RUBY-1985 Add SDAM test for debouncing topology description updates
-
- Closed
-
- links to