This topic describes the features, application scenarios, usage notes, precautions, and configurations of the maintenance window of a Service Mesh (ASM) instance.
Features and scenarios
ASM performs automatic maintenance tasks on the managed control planes of ASM instances as needed.
As described in the Support for Istio versions topic, ASM may automatically perform a hot update of a patch version for the managed control plane of an ASM instance. It aims to provide security patches and fix issues.
ASM periodically rotates the access credential for the managed control plane to access clusters on the data plane. This ensures the secure and stable operation of ASM.
You can use the maintenance window of an ASM instance to control the automatic maintenance time of the managed control plane of the ASM instance. This can mitigate latencies caused by configuration updates. You can use a maintenance window in the following scenarios:
During off-peak hours when traffic is low or no release tasks are performed, you can use a maintenance window to schedule automatic maintenance to minimize the impact on your business.
Suppose you use a maintenance window to perform automatic maintenance during working hours. In that case, you must assign a dedicated person to monitor the maintenance so that exceptions can be handled in time.
Usage notes and precautions
When ASM performs automatic maintenance tasks on the managed control plane, if you start a new proxy in a cluster on the data plane or update the ASM configuration, latencies in seconds may be caused.
The following limits apply to maintenance windows:
Only one maintenance window can be configured for an ASM instance. If a new maintenance window is configured, the new maintenance window overwrites the configuration of the previous maintenance window.
The time shown in a maintenance window is displayed based on the UTC+8 time zone.
Configure a maintenance window
Log on to the ASM console. In the left-side navigation pane, choose .
On the Mesh Management page, click the name of the ASM instance. In the left-side navigation pane, choose .
In the Config Info section on the Base Information page, click Edit on the right side of Maintenance Window.
In the Maintenance Window dialog box, set Maintenance Cycle, Maintenance Start Time, and Maintenance End Time, and then click OK.
The ASM instance temporarily enters the updating state. When the Status of the ASM instance becomes Running, the update is complete.
The following figure shows that the automatic maintenance task is performed from 00:00:00 to 04:00:00 from Monday to Friday.
