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Re: Ethernet Bridging



fixed

In your diagram replace the (GUEST) with a second instance of (HOST) and there you have it. So your first statement is correct, just put the two virtual LAN adapters on the same VLAN. Do be sure to use the correct one for each task of course because one of them is set for bridging when configured via the HMC and the second is not. Get them reversed and nobody on the inside talks to a anybody on the outside.

DrFranken

Sent from my iPad

On Aug 20, 2013, at 3:19 PM, Evan Harris <auctionitis@xxxxxxxxx> wrote:


In this scenario, how are the two virtual LIND's connected ? I'm guessing
you connect them by putting the virtual adapters on the same VLAN.

I have found that it is enough to specify the VLAN on the virtual adapter
that forms the virtual part of the bridge on the host. Adding a virtual
adapter into the same VLAN on the guest completes the connection. Like so:

Network <--> Phy Adapter <- bridge ID -> Virt Adapter (HOST) <- VLAN ID ->
Virt Adapter (GUEST)



On Wed, Aug 21, 2013 at 6:48 AM, DrFranken <midrange@xxxxxxxxxxxx> wrote:

So would that be a total of 3 lines on the first lpar? #1-physical
network bridged to #2-virtual LIND, and #3-virtual LIND with LPAR#1's
intended IP address.

Yes! The first two lines pair up and create the Bridge while the third
line is the line used for IP on the host partition.

Advanced option is to create an EtherChannel to the switch using two
physical Ethernet ports and cables. This gives some redundancy and
additional bandwidth as well. For best redundancy you'd want these to be
different physical Ethernet adapters as well.


- Larry "DrFranken" Bolhuis

www.frankeni.com
www.iDevCloud.com
www.iInTheCloud.com

On 8/20/2013 2:39 PM, Mitchell, Dana wrote:

Thanks Doc!

<Quote>
You can use just one physical line on the IBM i Host partition and have
that bridge to the desired internal VLAN. Then you can put a virtual
adapter on the host partition to that VLAN as well. The IP traffic for the
host then goes to the internal VLAN and then back out across the bridge.

The bridge itself appears to use virtually no CPU at all as long as you
follow IBMs recommendations.
</Quote>

So would that be a total of 3 lines on the first lpar? #1-physical
network bridged to #2-virtual LIND, and #3-virtual LIND with LPAR#1's
intended IP address.

This would be a good tidbit to include in the article along with IBM's
warning of what *not* to do....

Dana

-----Original Message-----
From: midrange-l-bounces@xxxxxxxxxxxx [mailto:
midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of DrFranken
Sent: Tuesday, August 20, 2013 12:23 PM
To: Midrange Systems Technical Discussion
Subject: Re: Ethernet Bridging

First discontinuing the HEA was essentially unintentional. When they got
to the point where it was no longer supported they couldn't put it back.
Besides the HEA had other weird limitations of it's own. Future stuff
may fill that gap but it's done now so.....

As to bridging it works great and it's not just for 3 or more LPARs, it
works with 2 as well (or actually even 1!) And with the right magic
incantations the bridge with allow IBM i to use 802.1Q VLANs too!

As you read, DO NOT put an IP address on the bridge itself. This is bad
and will burn CPU especially should you attempt any comm trace. At least
IBM lets you, put an address on a bridge in Cisco gear and you shut down
the bridge!

Remember it's the bridge operating in promiscuous mode so that it can
learn who's on the inside and who's on the outside so it can bridge all
'interesting' packets and ignore the others that causes the issue here.
Because the adapter is seeing every packet if there is an IP address
there then IP gets the packets too and that's a lot of extra work.

You can use just one physical line on the IBM i Host partition and have
that bridge to the desired internal VLAN. Then you can put a virtual
adapter on the host partition to that VLAN as well. The IP traffic for the
host then goes to the internal VLAN and then back out across the bridge.

The bridge itself appears to use virtually no CPU at all as long as you
follow IBMs recommendations.

- Larry "DrFranken" Bolhuis

www.frankeni.com
www.iDevCloud.com
www.iInTheCloud.com
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Regards
Evan Harris
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