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L2 to L3 issue

I have two networks with these subnets:



each of the subnets connected to a C6509 core switch ending with two core 6509s (both networks are separated geographically). the first network run with L2 configurations (VLANs, trunks, ..etc) whereas the other network ( run on L3 config with OSPF. However, there is L3 routing between the two C6509 core switches and 10.30 network is accessed from 10.10 network. My question, I have a PC in 10.10 network and I need to have an IP add from 10.30 subnet to be able joning the domain of 10.30 network. by the way, the PC is connected to C4507 access switch then to the core C6509 switch. What is the needed configuration on my side to access the 10.30 network for this PC only?


Re: L2 to L3 issue

hello sharaf,

If i understand right, ur 10.10 subnet is a L2 VLAN and 10.30 subnet is a L3 configured on the 6509 switch.. is that right ? If this is the case for any communication from the 10.10 to 10.30, you also need to configure a layer 3 interface for 10.10 on the 6509 to do intervlan routing.. Any L2 VLAN talks only to the PCs on the same subnet. If the PC wants to join to a domain server in 10.30 subnet, the switch needs to do intervlan routing, which isnt possible with L2 VLANs.

Best way to go about is, u can configure L3 interface for 10.10 VLAN on the 6509 and configure VACLs on the switch to allow only one PC to access the 10.30 VLAN. Rest of the access is blocked. VACL - VLAN Access control list, can block both Layer 3 and layer 2 packets...

hope this helps.. all the best. rate replies if found useful..


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