docs: disable and remove cdn unit (#5853)

Author: sguiheux

docs/content/hosting/upgrade/migrate_0.49.md

@@ -0,0 +1,50 @@
+---
+title: "Migrate 0.49"
+weight: 1
+---
+
+## CDN service
+
+The release 0.49 introduced a new parameter in CDN configuration to disable and remove a CDN unit.
+In the previous version 0.48, you migrate log from CDS to CDN, by adding a temporary CDN Unit [here]({{< relref "/hosting/upgrade/migrate_0.48.md" >}}). Time is coming to disabled it.
+In the next release (0.50), all logs datas in CDS will be deleted, and CDN will become the only way to manage logs.
+
+
+# Disable CDS Unit
+
+Add in your cdn configuration, the property "disableSync = true" for the CDS Unit
+
+```toml
+[cdn.storageUnits.storages.cds-backend]
+    syncParallel = 6
+    disableSync = true
+    [cdn.storageUnits.storages.cds-backend.cds]
+        host = "https://<your.cds.api>"
+        token = "<your.token>"
+```
+
+# Remove CDS Unit item from CDN Database
+
+To remove CDS Unit items, follow these steps:
+
+* Disable CDS Unit in CDN
+* Retrieve CDS Unit identifier usings cdsctl 
+
+```sh
+cdsctl -c prod admin cdn unit list
+```
+   * Mark CDS Unit item as delete using cdsctl
+```sh
+cdsctl admin cdn unit delete-items <unit_id>
+```
+
+# Remove CDS Unit from CDN Database
+
+To remove CDS Unit from CDN, follow these steps:
+
+* Remove all CDS Unit items from CDN database
+* Remove the unit using cdsctl
+
+```sh
+cdsctl admin cdn unit delete <unit_id>
+```