It's a problem with VMWare 4.1 and lower - VMWare freaks when it sees the same name with different ip addresses and does that. Using an individual ip is the only way we found to deal with it - we ended up using 2 of them (we ended up with nfsprod (1) and nfsprod (2)) to try to spread the load out a little (at the cost of halving the number of hosts to DRS to). Luckily, it was an older cluster that we were migrating out of, so not much of an impact.  5.0 and up can handle it correctly by dns name, fwiw.
Hi,   Today we presented  the first nfs  from x400 isilon to one of ESX host, then vmware admin try to mount it added 5 copies of same mount with nfsprd & nfsprod (1) & nfsprd (2) ..nfsprod (4) . we have 5 nodes in cluster with single dns name so issue here is when he mounted with  isilon_DNSname:/ifs/nfsprod it coming as 4 duplicated copies each for one node ip  but when he try to mount it with single node ip like  112.34.123.11:/ifs/nfsprod [ 112.xx.xx.xx  - node1 ip ] then it mounted as single mount point  so round robin is the issue here ? how to mount as single copy with isilon dns name ?  any help is appreciated.
Isilon NFS mount - ESX