Experiencing sync issues between different nodes in the same datacenter in Cassandra. The keyspace is set to a replication factor of 3 with NetworkTopology and has 3 nodes in the DC. Effectively making sure each node has a copy of the data. When node tool status is run, it shows all three nodes in the DC own 100% of the data.
Yet the applied_migrations column family in that keyspace is not in sync. This is strange because only a single column family is impacted within the keyspace. All the other column families are replicated fully among the three nodes. The test was done by doing a count of rows on each of the column families in the keyspaces.
keyspace_name | durable_writes | strategy_class | strategy_options
--------------+----------------+------------------------------------------------------+----------------------------
core_service | True | org.apache.cassandra.locator.NetworkTopologyStrategy | {"DC_DATA_1":"3"}
keyspace: core_service
Datacenter: DC_DATA_1
=====================
Status=Up/Down
|/ State=Normal/Leaving/Joining/Moving
-- Address Load Tokens Owns (effective) Host ID Rack
UN host_ip_address_1_DC_DATA_1 3.75 MB 256 100.0% 3851106b RAC1
UN host_ip_address_2_DC_DATA_1 3.72 MB 256 100.0% d1201142 RAC1
UN host_ip_address_3_DC_DATA_1 3.72 MB 256 100.0% 81625495 RAC1
Datacenter: DC_OPSCENTER_1
==========================
Status=Up/Down
|/ State=Normal/Leaving/Joining/Moving
-- Address Load Tokens Owns (effective) Host ID Rack
UN host_ip_address_4_DC_OPSCENTER_1 631.31 MB 256 0.0% 39e4f8af RAC1
Query: select count(*) from core_service.applied_migrations;
host_ip_address_1_DC_DATA_1 core_service applied_migrations
count
-------
1
(1 rows)
host_ip_address_2_DC_DATA_1 core_service applied_migrations
count
-------
2
(1 rows)
host_ip_address_3_DC_DATA_1 core_service applied_migrations
count
-------
2
(1 rows)
host_ip_address_4_DC_OPSCENTER_1 core_service applied_migrations
count
-------
2
(1 rows)
Similar error is received as described in the issue below. Because all the rows of data are not available, the migration script fails because it is trying to create an existing table: https://github.com/comeara/pillar/issues/25