Mongomirror failing to establish connection from AWS to Atlas

Hello Mongo Support,

We want to migrate our community mongo databases running on AWS to Atlas Cluster . Since it will be a different version movement(3.2 → 5.0) , We would like to make use of mongomirror utility to do a near to zero downtime migration.

However the mongo dbs on AWS are running on Docker containers.
What will be the exact syntax to specify the source host address .

/mongomirror --host replsetname\ip:port,ip:port,ip:port
–username xxxx
–password xxxx
–authenticationDatabase admin
–destination clusterxxx-shard-00-00.xxxx.mongodb.net:27017
–destinationUsername xxx
–destinationPassword xxx
–includeDB=xxx
–ssl
–forceDump

is giving me error
2023-08-08T12:31:09.332+0000 Error initializing mongomirror: could not initialize source connection: could not connect to server: server selection error: server selection timeout, current topology: { Type: ReplicaSetNoPrimary, Servers: [{ Addr: xxx:27017, Type: Unknown, Last error: connection() error occured during connection handshake: EOF }, ] }

Any idea how to achieve this.
Thanks

Any update on this. Will be really appreciated

Thanks