What are the advantages of a VLAN to a server admin?

You can move files across the VLAN from one server to another. This is good for backing up your data, or for when you need to upgrade servers (minimal downtime).

Depends in what context, a VLAN is many things.

If were talking Dedicated Servers - usually means your servers can be in there own VLAN - so traffic inbetween them isnt counted - plus it is more secure - as traffic inbetween the vlans cannot be snooped by someon on the same network segment.

Greetings:

That's an interesting question given the infrastructure is not presented.

Presuming two or more servers where the servers function as a team (i.e. mail server, database server, Web server, etc.), then a VLAN allows for zero bandwidth work between the servers.

The data transfer rate is also typical higher as well.

Thank you.

Dynamicnet - if there is no bandwidth being used - then there is no data being transferred :)

Assuming the host only counts traffic in+out of the vlan - as apposed to within the vlan - then yes - no bandwidth will be counted when transferring data between two servers.

Thanks everyone. So it is really only beneficial when having multiple machines within the same VLAN?

I think they also help prevent people from stealing your IPs.

VLAN's serve a number of purposes. Some significant ones, as they relate to dedicated servers are:

i) Isolated Broadcast Domain - By confining servers to their own individual broadcast domain, you will not see server broadcast traffic other than your own (or other servers within that VLAN)

ii) Bandwidth Utilization - Coupled with eliminating the 'extra' traffic that you would normally see on an interface from erroneous broadcast traffic, VLANs allow for more accurate billing of bandwidth usage/utilization.

iii) IP Security - By segregating individual systems, and allocating subnets per VLAN, the chances of another server or person 'stealing' IP's from your subnet, inadvertantly or malicously, are drastically reduced.

Regards,

Anthony summed it up pretty well, they are the major three advantages along with better security.