Now that you have logical partitions on your IBM System i5™ or eServer™ i5 server, you still want your logical partitions to communicate as they did on your iSeries™ 8xx server. However, instead of selecting the virtual Ethernet connections you want to use, you must select a slot location for each virtual Ethernet adapter. With virtual Ethernet adapters in a slot location, the server firmware knows the virtual LAN ID for each of the logical partitions on the server. Regardless of the number of slots in a logical partition or the slot location of the virtual Ethernet adapter, logical partitions can communicate with each other as long as they are sharing the same virtual LAN ID.
Your existing iSeries 8xx
server has three logical partitions. The primary partition and partition LPAR
372 are able to communicate with each other because they share a virtual LAN
ID of 0. The primary partition and partition LPAR 370 are able to communicate
with each other because they share a virtual LAN ID of 2. The primary partition,
partition LPAR 370, and partition LPAR 372 are able to communicate with each
other because they share a virtual LAN ID of 5. 
You will notice that the virtual LAN IDs on your existing logical partitions increased by one because the server automatically adds 1 to each of the virtual LAN IDs. The virtual LAN ID of 0 is no longer supported on IBM System i5 and eServer i5 servers. All IBM System i5 and eServer i5 servers support virtual LAN IDs 1 to 4096. The primary partition was renamed LPAR 180 because IBM System i5 and eServer i5 servers do not support a primary partition.
Partition LPAR 370 and partition LPAR 180 are able to communicate because they now share the same virtual LAN ID of 3. Partition LPAR 372 and partition LPAR 180 are able to communicate because they now share the same virtual LAN ID of 1. And partition LPAR 370, partition LPAR 372, and partition LPAR 180 are still able to communicate because they share the same virtual LAN ID of 6.
After successfully converting your existing virtual Ethernet configuration, you are now ready to create your Ethernet line descriptions and decide how you want to connect to an external LAN using different TCP/IP techniques. For more information about how to create Ethernet line descriptions and how you connect a virtual Ethernet network to an external LAN, refer to TCP/IP techniques to connect virtual Ethernet to external LANs.