I am getting below error while using AWS data migration service.
Source - One single postgres rds instance having multiple databases in it (80 GB)
Target - One single postgres rds instance where each src database will be a schema in same database
Number of tables - Total number of tables including all databases is around 200
Replication instance - t2.medium
I created four tasks for replicating four databases from source into four different schemas in target. But the fifth task for fifth database is failing with below error -
ERROR: all replication slots are in use;, Error while executing the
query
How can I increase the replication slots so that dms can have 10 tasks running together?
Found the answer, There is an option to configure maximum number of replication slots in aws postgres rds instance which should solve my issue.
Related
I have several postgres databases which need to be replicated as-is to a single aws redshift.
We have currently set up DMS services to the same. However, we keep encountering issues such as source database full, large column issues and most importantly the issue in DMS when new columns with defaults are added on postgres databases(This does not replicate with ongoing replication)
So, are there any other ways that we can set up this ongoing replication?
I created a DMS task:
Source - MongoDB
Target - RDS Postgres
I have successfully working pipelines with full load + Ongoing replication working.
But for some collections in my source mongo when I create Full load or Full load + Ongoing replication,
Task shows successfully completed and starts ongoing replication.
But Full load doesn't happens only schema gets created in postgres with 0 rows, and Ongoing replication starts.
CloudWatch shows no error even after detailed debug.
In our case it's because of wrong database name configuration in DMS mongoDB endpoint. The table creation and CDC still work, but full load fails.
I have a partitioned table in RDS1 (version 10) that I want to replicate to another RDS postgres (version10)
I'd like to know if it's possible. If yes, what would be the method that I should apply ?
The data should be replicated in real-time, very low latency. Partitions in the master are added and removed in daily basis.
The motivation for the replication is to reduce load from the master db.
Thanks!
We have a replication setup from AWS RDS PostgreSQL to Kafka. The replication slot's restart_lsn is not moving and WALs keep pilling up.
I tried to remove all the Kafka replications and tried using logical replication and AWS DMS on the same postgreSQL instance, that too doesn't release it's position in WAL,Even though the changes are getting replicated to the target. Why replication slots are holding these WALs?
I have a requirement of replicate data from AWS RDS Postgres(9.6) Database to On-Premise Postgres(9.5) Database. I have found stuff about replication from On-premise to On-premise. But How can we implement it for AWS RDS to On-premise?
I do this using Bucardo.
Check-out this: https://bucardo.org/Bucardo/
With Bucardo you can replicate RDS postgres instance to a slave postgres present somewhere, only configuring slave, so without the needs to configure RDS stuff.
Also you can do this with zero downtime.
Anyway I am not sure this will work using different versions of Postgresql. You should use same version if possible. I tested it with 9.4.x and it is working.
UPDATE
I can confirm that this is working also using different version of Postgres, for example I was able to replicate with these versions:
AWS RDS postgresql 9.4.x
On-premise postgresql 9.6.x
http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/CHAP_PostgreSQL.html#PostgreSQL.Concepts.General.FeatureSupport.LogicalReplication
Beginning with PostgreSQL version 9.4, PostgreSQL supports the
streaming of WAL changes using logical replication slots. Amazon RDS
supports logical replication for a PostgreSQL DB instance version
9.4.9 and higher and 9.5.4 and higher. Using logical replication, you can set up logical replication slots on your instance and stream
database changes through these slots to a client like pg_recvlogical.
Logical slots are created at the database level and support
replication connections to a single database.
mind possible problems eg https://dba.stackexchange.com/questions/173267/aws-rds-postgres-logical-replication