That's only actually required if you have multiple paths between the E2K3 and E2K10 routing groups. In the original post, only a single E2K3 server and a single E2K10 server was quoted, so I personally wouldn't bother with this.
From: Michael B. Smith [mailto:mich...@smithcons.com] Sent: 26 March 2010 18:23 To: MS-Exchange Admin Issues Subject: RE: Exchange 2010 install w/coexisting E2K3 Organization Yessir. Regards, Michael B. Smith Consultant and Exchange MVP http://TheEssentialExchange.com From: John Bowles [mailto:john.bow...@wlkmmas.org] Sent: Friday, March 26, 2010 2:11 PM To: MS-Exchange Admin Issues Subject: RE: Exchange 2010 install w/coexisting E2K3 Organization One question I have for you though.. should I suppress link state routing prior to performing this? From: Michael B. Smith [mailto:mich...@smithcons.com] Sent: Friday, March 26, 2010 1:49 PM To: MS-Exchange Admin Issues Subject: RE: Exchange 2010 install w/coexisting E2K3 Organization Sure have. It was very common in 2007 migrations and only slightly less so in 2010 migrations. Just create the Interop-RGC. Regards, Michael B. Smith Consultant and Exchange MVP http://TheEssentialExchange.com From: John Bowles [mailto:john.bow...@wlkmmas.org] Sent: Friday, March 26, 2010 1:47 PM To: MS-Exchange Admin Issues Subject: Exchange 2010 install w/coexisting E2K3 Organization All- I installed an Exchange 2010 server into an Exchange 2003 organization(1 E2K3 server, 1 E2k10 server). All the pre-req's passed with no problems, exchange installed fine. One issue is that when Exchange 2K10 was installed it didn't create RGC between to the two servers, also the E2K10 server doesn't show up in the created admin group during installation. So no, I cannot replicate PF's or send mail between servers. Has anyone seen this behavior before? Thank you, John Bowles