02-07-2012 09:22 AM
So, I am obviously new to the Brocade\Foundry world... I am trying to make sense of something, and was wondering if I could get clarification...
OK, so if I want to assign specify a particular VLAN to a interface, I would issue the command tagged eth X under that VLAN... That makes sense, and if I wanted to ensure that a certain VLAN was sent across a link untagged, I would issue a command untagged eth X under the desired VLAN... that also make sense. Now if I want to setup a VLAN to be a Layer 3 VLAN, then I simply enter the command routed-interface ve X under the VLAN and, under the interface ve X command, assign an IP... All this I get. What I don't get is the purpose of the following:
Why would I assign a subnet to a VLAN with the ip-subnet command? Doesn't the ve interface accomplish this by linking a L3 address to the VLAN?
Also, within the ip-subnet command, what is the purpose of the static ethe X command? Is, under a VLAN, the command tagged eth X command not accomplish this...? Why would I assign a vlan to a interface using the static command if I have already dictated what VLANs are assigned to what interfaces under the VLAN itself?
Sorry for the noob questions... I appreciate your help!
02-07-2012 01:32 PM
You are correct in that adding Router interface VE will add the L3 subnet to the VLAN. You do not ned the ip subnet command or the static ethernet for this.
In fact I have never used this command, so had to look up what it does Both of the commands you are asking about work together for the below.
Configuring IP subnet, IPX network and protocol-based VLANs
Protocol-based VLANs provide the ability to define separate broadcast domains for several unique Layer 3 protocols within a single Layer 2 broadcast domain. Some applications for this feature might include security between departments with unique protocol requirements. This feature enables you to limit the amount of broadcast traffic end-stations, servers, and routers need to accept.
Suppose you want to create five separate Layer 3 broadcast domains within a single Layer 2 STP broadcast domain:
• Three broadcast domains, one for each of three separate IP subnets
• One for IPX Network 1
• One for the Appletalk protocol
Also suppose you want a single router interface to be present within all of these separate broadcast domains, without using IEEE 802.1Q VLAN tagging or any proprietary form of VLAN tagging.