how to login a cluster with robin DNS by ssh

Question

There is a cluster named "xxxx.com" with robin DNS.

dig xxxx.com gives:

xxxx.com 3600 IN A aaa.bb.c.dd1

xxxx.com 3600 IN A aaa.bb.c.dd2

dig -x aaa.bb.c.dd1 gives:

dd1zzzzzzzz 3600 PTR xxxx.com

dd1zzzzzzzz 3600 PTR xxxx1.com

and

dig -x aaa.bb.c.dd2 gives:

dd2zzzzzzzz 3255 PTR xxxx.com

dd2zzzzzzzz 3255 PTR xxxx2.com

My question is: if I just want to login by command ssh username@xxxx.com without any error, what should I do?

PS: I found the key of xxxx1.com and xxxx2.com are different.

Thank you in advance.

Answer 1

In SSH you can specify multiple identity files.

ssh -i /path/to/key1 -i /path/to/key2 username@xxxx.com

and if you dont want to type -i options everytime, create ~/.ssh/config file as below

Host yyy
  Hostname xxxx.com
  User username
  IdentityFile /path/to/key1
  IdentityFile /path/to/key2

and you can always login using

ssh yyy