Is the only benefit of LCM then that it can deploy updated configs from the ui?
No. It automates Java and JCE policy installation. It automates certificate generation and distribution for node-to-node and client-to-node encryption. It automates cluster registration and integration with OpsCenter to allow easy/GUI metrics backups and repairs. It simplifies deloyments in offline environments by integrating with proxies, custom-download-locations, and apt/yum mirrors. It handles a large list of rough edges like that that apt-command-line I noted previously. It codifies a heap of best practices to prevent you from stumbling into unnecessary problems.
It also provides the most comprehensive API in existence to DSE parameters, covering all non-eol DSE versions and nearly every documented parameter for each version, and unlike Ansible and Chef does not require customers to maintain config-file templates for each DSE version. It doesn't handle this use case, right now. It does handle many other use-cases, and the number of covered cases grows with each release. All this is covered in our documentation at docs.datastax.com/en/opscenter/6.1/opsc/LCM/opscLCM.html
> It handles a large list of rough edges like that that apt-command-line I noted previously. < does it? cause those apt commands have to be run manually anyway to upgrade those instances. so scripts will have to be written either way. unless you never upgrade your instance