On 1/8/09 6:09 PM, "KEETON Dave * SDC" <[email protected]> wrote:
> I have need for multiple VLAN memberships also. I keep running into > issues with routing when I have more than one VLAN configured. Does > anyone have any pearls of wisdom in this area? Any docs for advanced > VLAN networking with VSWITCH under z/VM 5.4? Working on some stuff for a future conference. Nothing to share yet. > Scenario: If you had an environment that consisted of Administration, > Production networks and you wanted a guest to participate in both, > wouldn't you just create two VLAN memberships to eth0 (ala vconfig)? Or > would it be prudent to create a separate VSWITCH for Administration and > Production and use eth0 and eth1 nics (using the PORTTYPE ACCESS > method)? You can do either technically, but I suspect it will be simpler and easier to audit if you create separate VSWITCHes for each network. The main use for multiple VLANs on the same interface is to save hardware costs (adapters and switch ports); with virtual hardware, that problem really doesn't exist, so keeping things simple by having multiple switches and interfaces is easier to manage. That approach also lets your ESM control and audit who is connecting to what -- if you give a trunk port to a guest, you are relying on the admin of that guest to behave and not tag things for or connect to the wrong VLAN. Yes you can limit that in the switch, but that's going to make your networking people twitchy and cranky -- not a desirable outcome.
