Hi,
If I understand it correctly the remote stations have DDNS and ASA needs to communicate with them.
We just need to make sure ASA is able to resolve the hostnames for these remote stations.
The access-rules on the ASA would be configured on the basis of the FQDN's for these stations as they would keep on changing their IP's.
If ASA is able to resolve them I do not think there would be any issue.
Regards,
Aditya
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