Sync docs from Discourse (#226)

Sync charm docs from https://discourse.charmhub.io

Co-authored-by: GitHub Actions <41898282+github-actions[bot]@users.noreply.github.com>

Author: github-actions[bot]

docs/how-to/h-rollback-major.md

@@ -0,0 +1,15 @@
+# Upgrade
+
+**In-place upgrades/rollbacks are not possible for major versions.**
+
+> Canonical is not planning to support in-place upgrades for major version changes. The new MySQL Router K8s charm will have to be installed nearby, and the data will be copied from the old to the new installation. After announcing the next MySQL major version support, the appropriate documentation for data migration will be published.
+
+For instructions on carrying out **minor version upgrades**, see the following guides:
+
+In-place minor upgrade:
+
+* [Minor upgrade](/t/12345?channel=dpe/candidate), e.g. MySQL Router 8.0.33 -> MySQL Router 8.0.34<br/>
+(including charm revision bump 99 -> 102).
+
+* [Minor rollback](/t/12346?channel=dpe/candidate), e.g. MySQL Router 8.0.34 -> MySQL Router 8.0.33<br/>
+(including charm revision return 102 -> 99).

docs/how-to/h-upgrade-intro.md

@@ -47,21 +47,13 @@ This MySQL Router charm is an official distribution of MySQL Router. It’s an o
 | 2 | h-monitoring | [Monitoring]() |
 | 3 | h-enable-monitoring | [Monitoring (COS)](/t/14094) |
 | 3 | h-enable-tracing | [Tracing (COS)](/t/14785) |
-| 2 | h-upgrade | [Upgrade]() |
-| 3 | h-upgrade-intro | [Intro](/t/12342) |
-| 3 | h-upgrade-major | [Major upgrade](/t/12343) |
-| 3 | h-rollback-major | [Major rollback](/t/12344) |
+| 2 | h-upgrade | [Upgrade](/t/12342) |
 | 3 | h-upgrade-minor | [Minor upgrade](/t/12345) |
 | 3 | h-rollback-minor | [Minor rollback](/t/12346) |
 | 2 | h-contribute | [Contribute](/t/14656) |
 | 1 | reference | [Reference]() |
-| 2 | r-releases-group | [Release Notes]() |
-| 3 | r-releases | [All releases](/t/12318) |
-| 3 | r-releases-rev269 | [Revision 267/268/269](/t/16074)
-| 3 | r-releases-rev225 | [Revision 223/224/225](/t/15360)
-| 3 | r-releases-rev198 | [Revision 197/198](/t/14073) |
-| 3 | r-releases-rev119 | [Revision 118/119](/t/12319) |
-| 2 | r-requirements | [Requirements](/t/12325) |
+| 2 | r-releases | [Releases](/t/12318) |
+| 2 | r-system-requirements | [System requirements](/t/12325) |
 | 2 | r-testing | [Testing](/t/12324) |
 | 2 | r-contacts | [Contacts](/t/12323) |
 | 1 | explanation | [Explanation]() |
@@ -70,4 +62,14 @@ This MySQL Router charm is an official distribution of MySQL Router. It’s an o
 | 2 | e-juju-details | [Juju](/t/12320) |
 | 2 | e-legacy-charm | [Legacy charm](/t/15370) |
 
-[/details]
+[/details]
+
+<!--Archived
+| 3 | h-upgrade-major | [Major upgrade](/t/12343) |
+| 3 | h-rollback-major | [Major rollback](/t/12344) |
+
+| 3 | r-releases-rev269 | [Revision 267/268/269](/t/16074)
+| 3 | r-releases-rev225 | [Revision 223/224/225](/t/15360)
+| 3 | r-releases-rev198 | [Revision 197/198](/t/14073) |
+| 3 | r-releases-rev119 | [Revision 118/119](/t/12319) |
+-->