Thank you for your patience here. I got the response back from the team.
Thank you for reaching out. Based on your questions above.
How many ways migration can be performed (excluding portal) ?
Currently the migration is only possible via the portal.
Is their any downtime we will face during migration?
You can migrate existing connection monitors to new, improved Connection monitor with only a few clicks and with zero downtime. This is documented here.
What is the impact of this migration to other resources present?
The Agents and firewall settings work as is. No changes are required as documented here in this section here.
The following changes will happen after the migrations begins
The Azure Resource Manager resource changes to the newer connection monitor:
The name, region, and subscription of the connection monitor remain unchanged. The resource ID is unaffected.
Unless the connection monitor is customized, a default Log Analytics workspace is created in the subscription and in the region of the connection monitor. This workspace is where monitoring data is stored. The test result data is also stored in the metrics.
Each test is migrated to a test group called defaultTestGroup.
Source and destination endpoints are created and used in the new test group. The default names are defaultSourceEndpoint and defaultDestinationEndpoint.
The destination port and probing interval are moved to a test configuration called defaultTestConfiguration. The protocol is set based on the port values. Success thresholds and other optional properties are left blank.
Metrics alerts are migrated to Connection monitor metrics alerts. The metrics are different, hence the change. For more information, see Metrics in Azure Monitor.
The migrated connection monitors are no longer displayed as the older connection monitor solution. They're now available for use only in Connection monitor.
How the extension are installed to the virtual machine when we haven't installed it ?
In case virtual machines used as sources in Connection monitor (classic) no longer have the Network Watcher extension enabled, you get an error message stating "Connection monitors having following tests cannot be imported as one or more Azure virtual machines don't have network watcher extension installed. Install Network Watcher extension and click refresh to import them." In this case you will have to install the extension manually. This documented in the prerequisites here.
Hope this helps! Please let me know if you have any additional questions. Thank you!
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