We have 5 nodes running in 3 different data centers with replication set to 3 in each. We use XDCR to keep the data centers consistent with each other. However in one of the data centers we are seeing a a particular document exists but it does not exist in the other 2. Under what circumstances will XDCR not be consistent? Are there any suggestions to fix this problem?
Version: 4.5.1-2844 Community Edition (build-2844)
Yes @firstname.lastname@example.org we use bidirectional replication. It has been recommended that we change our replication to 2 from 3 and we will do this. However, I fail to see how this would cause the issue we are seeing. Any other suggestions are welcome.
Assuming the three clusters each of 5 nodes topology @unhuman suggested, I can’t think of any reason a particular document would not replicate to the other clusters. I’d probably recommend verifying the replication is configured as expected. If so, then have a look at the XDCR logs to see if there is a clue.
One common problem, if it is across something like EC2 regions, may be blocked ports. That could cause this. Ports 8091 and 11210 for sure need to be open between the clusters.
@k_reid I am an engineer from xdcr team. It would be helpful if you could attach the goxdcr.log files from all three clusters. It would also help to extract the metadata of the document involved from the cluster where it is present, e.g., through couch_dbdump.