I have two sites in a multi-site cluster. 7 peers in each site. I have been running this configuration for two years. Over the last couple months I've begun to notice that one site has been adding more buckets that the other. In approximate numbers, site1 has 203,000 buckets. Site2 has 175,000 buckets. I've run rolling-restart a couple times and data rebalance too. I've searched for troubleshooting tips for situations like these but I have not turned up much useful information. My forwarders (heavy and universal) are configured to auto balance across all peers. I'm on version 7.04 and have been there since shortly after its release. What is going on? Thank you for your consideration.
I think the issue here is Splunk try to achieve 90% rebalancing not fully 100%. If you want 100% rebalancing on both the sides, then you can achieve that as well using the below command:
splunk edit cluster-config -mode master -rebalance_threshold 1 -auth admin:your_password
The below link can help you better: