Is it okay to have two different name servers with the same ip's?

I have set some nameservers to the same IP address, but these were during a transfer. I did have NS3 and NS4 the same as NS1 and NS2, but had at least 2 different IP's assigned. It would not be good if all the nameservers were the same.

 

Perhaps...

Wrong example:
ns1.mydomain.biz = 60.xx.xxx.xxx
ns2.mydomain.biz = 60.xx.xxx.xxx
ns3.mydomain.biz = 60.xx.xxx.xxx
ns4.mydomain.biz = 60.xx.xxx.xxx
where x = same numbers.


Yes example:
ns1.mydomain.com = 60.xx.xxx.xxx
ns1.mydomain.net = 60.xx.xxx.xxx
ns1.mydomain.org = 60.xx.xxx.xxx
ns1.mydomain.biz = 60.xx.xxx.xxx
where x = same numbers.