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Customizations to an Elasticsearch 6.8.6 /etc/elasticsearch/elasticsearch.yml path.data and network.host fields will be lost when running the configuration script to upgrade to Elasticsearch 7 if the upgrade does not complete. This can happen if the new Elasticsearch 7 rpm is not in the current directory and cannot be downloaded. Reapply your customizations as this will not affect upgrades starting with Elasticsearch 7.5.2. (SWAR-9977)
False 404s might be seen in the Swarm responses during heavy load situations. To mitigate this, please verify “cip.processes = 2”, and keep increasing the cip.queryMinimumTimeout value gradually until the 404 occurrences are reduced. (SWAR-10120)
When using search.perDomainIndex=True (under Support guidance), the number of supported domains is limited based on the number of data nodes in the Elasticsearch cluster and search.numberOfShards. For example, Five five data nodes support 5x600 shards at search.numberOfShards=65; each domain requires 6x2 5x2 (primary and replica) shards. If more than 250 domains are created, new Also remember Gateway creates daily csmeter indices, 1 shard x 2 each, for 90 days. So the maximum number of domains supported is about 280. After that new domain indices cannot be created resulting in the a domain listing that returns returning a 503 ReaderUnavailableIndex. The castor.log will show errors EFD19, EIP15, and EIP02.
For example, "Validation Failed: this action would add [6] shards, but the cluster currently has maximum [999]/[1000] normal open shards". Error reporting will be improved in a future release. (SWAR-10172)
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