Today’s top server hardware vendors have expanded the line of Linux compatible server systems. HP and Dell, for example, have Red Hat Enterprise Linux (RHEL) and Novell SUSE Enterprise Linux available as OEM build installations, the same hardware that a Windows server can be built on. As recommended configurations from the vendors are quite similar, this can make any server purchases a little easier to swallow. Because configurations are similar for Windows and Enterprise Linux builds, these servers can be repurposed to change their roles to Windows or Linux without additional equipment.
Take for example the HP ProLiant DL 380 G5 and the Dell PowerEdge 2950 III, which can be configured for a general purpose Windows or Linux server and can have most connectivity options available: fiber networking interfaces, storage area network (SAN) fiber channel adapters and any additional copper networking. The local drive configurations currently use serial attached SCSI (SAS) drives with local array controller.
Dell and HP generally divide models by Intel and AMD processor offerings, so the selection process is aided by that distinction. If you strive for a common server for the Enterprise Linux builds and the Windows server space, a uniform processor brand platform is a must.
If you embark on the single server across software groups, be sure to get all members on board and mutually agree on a server specification. If the needs are different, it may be more likely to work in terms of base server and customize up as required. This can save the incremental cost of a small number of under-utilized servers in a mixed environment.