Specifications

Administration Guide
280 VMware, Inc.
Applications that Can Use Clustering
To!take!advantage!of!clustering!services,!applications!need!to!be!able!to!recongnize!
clustering.!
Such!applications!can!be:
! Stateless,!as!are!Web!servers!and!VPN!servers!.
! With!built‐in!recovery!features,!like!those!in!database!servers,!mail!servers,!file!
servers,!or!print!servers.
Clustering Software
Available!clustering!software!includes:
! Microsoft!Clustering!Service!(MSCS)
Provides!fail‐over!support!for!applications!such!as!databases,!file!servers,!and!mail!
servers
! Microsoft!Network!Load!Balancing!(NLB)
Load!balances!incoming!IP!traffic!across!a!cluster!of!nodes!for!applications!such!as!
Web!servers!and!terminal!services.
! Veritas!Clustering!Service!(VCS)
Clustering Hardware
A!typical!clustering!setup!includes:
! Disks!that!are!shared!between!nodes.!Needed!if!the!application!uses!dynamic!data!
as!mail!servers!or!database!servers!do.
The!shared!disks!can!be!shared!SCSI!disks!or!a!storage!area!network!using!Fibre!
Channel.
! Extra!network!connectivity!between!nodes!for!monitoring!heartbeat!status.
! A!method!for!redirecting!incoming!requests.
Clustering Virtual Machines
ESX!Server!hosts!can!utilize!clustering!services!to!enable!the!clustering!of!virual!
machines!that!are!running!on!ESX Server!hosts.!Clustering!virtual!machines!allows!the!
virtual!machines!to!share!data!or!applications!across!multiple!virtual!machines.!Use!of!
clustering!services!in!virtual!machines!provides!high!availability!with!less!hardware!
(such!as
!machines!and!network!adapters).