Configuring OSPF on HP Gbe2c layer 2/3 switch in c3000 chassis

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Hello,

i have a HP blade environment with 3 BL460p blades in a C3000 chassis with 2 gbe2c layer 2/3 switches in interconnect bay 1 and 2 and 2 3G SAS switches in interconnects bays 3 and 4.
I want to create 4 networks on the layer 2/3 switch and route them to an ASA 5505 for internet using OSPF. I will also have a LAN attached to the ASA5505 as well in its own VLAN.
What i believe i will do is create 4 VLANS on the gbe2c and create 4 layer 3 IP interfaces. I then configure OSPF to route between them and with the ASA 5505 to get out to the inernet. So do I just need one OSPF Area for this simple environment? and can someone help me how to configure OSPF with my VLANS above on the gbe2c switch as well as route with the ASA5505? Anyone help will do. Thanks,

jimmy
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Yes you can do it with just one area. You probably don't need to use OSPF if all you are talking about is routing amongst the 4 subnets and getting to the Internet as mentioned. Just having IP routing enabled on the L3 switches will allow routing between the VLANs on the same switch. You only need other routes to get to the Internet and any networks behind other routers the local switch is not directly connected to. So your ASA would need a static route to each of the other 3 networks not in common with it and the HP. And the HP would need one static Default route pointing to the ASA to get to the Internet and anything else behind the ASA.

Author

Commented:
Thanks for the help Rick. Ok, if i dont need OSPF enabled on the Gbe2c swtich then what protocol would i need to use? You say to just enable IP routing where or how do i tell it to do that? or do you mean to just make static routes?  i am pretty new with a HP gbe2c interconnect switch but know routing basics. So you are also suggesting a static route on the ASA as well for the traffic from the gbe2c adn the directly connected VLAN on the ASA? Thanks,

jimmy
Hi Jimmy,

On some switches by adding IP to the VLANs interface it enables routing so anything from subnet inside the switch is routed automatically. On other switches you need to globally enable L3/routing and put IP addresses on the interfaces as well. Regardless of what way it is done it should take care of routing from VLAN to VLAN within the switch.
So then all you need is a couple of static routes to take care of routing outside the switch. If you already have one subnet common between the ASA and the HP you probably already have a static route on the HP to get to the Internet via the ASA. If that is the case all you need to do now is add a few statics to the ASA to get back to the new subnets on the HP.
A dynamic routing protocol like RIP or OSPF would not be necessary unless you have too many subnets, or more routers, or some other reason like multiple paths to networks that can't easily be managed statically.
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Author

Commented:
So on the Gbe2c switch, i just creat the 4 VLANs. Assign an IP interface to each VLAN and they will already be routing between eachother?
You need to turn IP forwarding on globally first.

Author

Commented:
Ok, so what i will do is create my 3 VLANs (The default 4056 is the 4th VLAN) and then assign an interface to all 4. Then turn on IP forwarding. I will then configure my VLAN on the ASA 5505 and create static routes from the ASA to the 4 VLAN so having 4 static routes. Does this sound right?  I will be trying this soon and will let you know how it goes. I also have a redundant switch question but i may put in another thread for that. Thanks,
jimmy
That sounds right.

Author

Commented:
Do you know where on the gbe2c Web interface i go to turn on IP forwarding?
I was looking at it in the command line but I will see if I can find it on web interface.

Author

Commented:
If you can also please inclue the command line one too. Thanks!
Browser:
Layer 3 - General
Then choose enabled

Command Line:
/cfg/l3/frwd
Then "on" to globally enable IP routing

Author

Commented:
hi rick, this just dawned on me. But can i have the VLANS created on the gbe2c and then trunk them to the Cisco ASA 5505 and create subinterfaces on there?
Yes if that model does subinterfaces that will work too. It just moves the routing out to the ASA vs doing it on the switch.

Author

Commented:
hmmm ok, would you suggest the routing be done on the gbe2c or do the trunking. Right now I am thinking of not putting the client LAN on the ASA and that on the Gbe2c. So if I do the whole trunking thing does that mean i dont need to enable IP Forwarding?
If you set up the routing to be done on the switch then you would still be operational except for the Internet if you lost the ASA. And the only thing going to the ASA would be traffic for the internet and whatever else is behind it vs all VLAN to VLAN traffic going through the ASA and its port on the switch.

If you do the routing on the ASA then you are correct you could keep the switch at layer 2 with just the VLANs running on it.

Author

Commented:
Thanks for your help Rick, I made 2 VLANs on the ASA 5505 and routing between them without OSPF. both VLANS are directly attached so not much routing commands involved.
jimmy
Glad to help.

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