Merge pull request 'Add readme to Upgrade Graylog and MongoDB to vers…

…ion 6.0.5 and 6.0.16 respectively' (#406) from grayLogUpgradeReadme into master

Reviewed-on: https://gitea.obmondo.com/EnableIT/KubeAid/pulls/406

argocd-helm-charts/graylog/upgrading.md

@@ -0,0 +1,29 @@
+## Backup Data
+1. **MongoDB Backup**: Use `mongodump` to back up the MongoDB data.
+2. **Elasticsearch Backup**: Back up Elasticsearch data
+3. **Graylog Configuration Backup**: Backup Graylog configuration and Helm `values.yaml`.
+
+## Review Breaking Changes
+1. **Plugins**: Verify all plugins for compatibility with Graylog `6.x` and replace/remove incompatible plugins.
+2. **Templates**: Review any custom templates and ensure compatibility with **JMTE 7.0.2**.
+
+---
+
+## Steps for the Upgrade:
+
+1. **Check Compatibility Matrix**: Review the compatibility matrix of Graylog and MongoDB from the official documentation:
+![Graylog MongoDB Compatibility Matrix](grayLogCompatibiltyMatrix.png)
+[Reference Link](https://go2docs.graylog.org/current/upgrading_graylog/upgrading_graylog.html?tocpath=Upgrading%20Graylog%7C_____0)
+
+1. **Upgrade MongoDB Operator**: Upgrade the MongoDB operator to the latest version **0.11.0**. Ensure the Helm charts are up to date with the upstream repository.
+
+2. **Remove Incompatible Plugins**: Remove or replace any incompatible Graylog plugins.
+
+3. **Add `data_dir` to Graylog Configuration**:
+   Add the `data_dir` in the `graylog.conf` (default: `/usr/share/graylog/data`) based on the values from the `values.yaml` file.
+
+4. **Add Startup Probe for Graylog**:
+   Configure a **startup probe** in the Graylog deployment to ensure Graylog starts only after MongoDB is ready.
+
+5. **Upgrade Graylog and MongoDB**:
+   Perform the upgrade of Graylog to version **6.0.5** and MongoDB to version **6.0.16** and sync.