Hi @SachinGargNTT
How long is the retention time of the existing M-100 appliance and how long is your company policy for the retention?
Actually on the link you provided, the solution is already written:
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This procedure assumes you are no longer using the M-100 or M-500 appliance for device management or log collection. If you plan on using the decommissioned M-100 or M-500 appliance as a Dedicated Log Collector, a device management license is required on the M-100 or M-500 appliance. Without a device management license, you are unable to use the M-100 or M-500 as a Dedicated Log Collector.
You may still access existing log data at a later date if you do not plan on using the M-100 or M-500 appliance as a Dedicated Log Collector. After you have successfully migrate to the new M-Series appliance, power on the M-100 or M-500 appliance to query and generate reports from the Panorama web interface of the decommissioned M-Series appliance. Palo Alto Networks recommends reviewing the log retention policy before decommissioning the M-100 or M-500 appliance.
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This means on your new appliance you can add the old log collector as a dedicated log collector that you use only for logqueries and not for writing new logs to it. This requires that the old appliance is still licensed otherwise you will not be able to continue to use it. Does this answer your question?
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