kubernetes deployment - user-defined persistent volumes

[mmguero]

Sub-issue of #149

while we're testing with some local nfs volumes, the user will need to define whatever kind of persistentvolume backing storage as they want. I'm not sure the best way to do this. My guess is that the easiest thing to do will be to require them to create and populate the contents of that 01-volumes.yml file themselves, and that they must define, using the same names, the volumes and volume claims in that example. Then those can get created and we can use them by those names.

[mmguero]

Here's what's going in the docs for this issue. We're just going to require the user to create it:

---

Malcolm requires persistent storage to be configured for its configuration and data files. There are various implementations for provisioning PersistentVolume resources using storage classes. Regardless of the types of storage underlying the PersistentVolumes, Malcolm requires the following PersistentVolumeClaims to be defined in the malcolm namespace:

• config-claim - storage for configuration files
• opensearch-backup-claim - storage for OpenSearch snapshots (if using a local OpenSearch instance)
• opensearch-claim - storage for OpenSearch indices (if using a local OpenSearch instance)
• pcap-claim - storage for PCAP artifacts
• runtime-logs-claim - storage for runtime logs for some containers (e.g., nginx, Arkime)
• suricata-claim - storage for Suricata logs
• zeek-claim - storage for Zeek logs and files extracted by Zeek

An example of how these PersistentVolume and PersistentVolumeClaim objects could be defined in the kubernetes/01-volumes.yml.example manifest file. Before running Malcolm, copy the 01-volumes.yml.example file to 01-volumes.yml and modify (or replace) its contents to define your PersistentVolumeClaim objects.

If you attempt to start Malcolm without these PersistentVolumeClaims defined in a YAML file in Malcolm's ./kubernetes/ directory, you'll get an error like this:

$ ./scripts/start -f /path/to/kubeconfig.yml
Exception: Storage objects required by Malcolm are not defined in /home/user/Malcolm/kubernetes: {'PersistentVolumeClaim': ['pcap-claim', 'zeek-claim', 'suricata-claim', 'config-claim', 'runtime-logs-claim', 'opensearch-claim', 'opensearch-backup-claim']}