HiWe are currently running Exchange 2003 SP2. The architecture on each server is set up so that each Business Unit has its own Storage Group, and sub-departments within that BU have their own store to take advantage of Single Instance Storage.We also have some offices outside the country, each with their own mailbox server. Since the WAN links have been upgraded, we were looking to pull in these mailboxes to the central Exchange servers in HQ.However - we will need to estimate how much extra space we need. The architecture in the remote sites is the same. My questions are:i) Can we use the sizes of the databases in the remote sites as a guide to what they will be like when they move to HQ? ii) Are there any tools/calculations we can run that will estimate how much space we need based on mailbox size, limits, deleted items retention etc?iii) Should we run any form of offline defrag (on either the remote or HQ Exchange servers) before or after the mailbox moves?iv) I hear that mailbox moves can cause large numbers of transactions logs, not sure if this is on the source of destination mailbox server? Is enabling circular logging advised? v) Once all mailboxes have been moved and a suitable time period passed, how do we remove the old Exchange servers from the Org? Just uninstall Exchange? vi) If there are public folders on the remote Exchange servers, how can these be moved to the HQ Exch boxes? vi) Any other points we should consider?

1>Can we use the sizes of the databases in the remote sites as a guide to what they will be like when they move to HQ? The sizes of database may slightly vary once you move the remote mailboxes to Central Server due to SIS 2> Are there any tools/calculations we can run that will estimate how much space we need based on mailbox size, limits, deleted items retention etc Refere below articlet to get more info. There are some third party tools available such as vendors like HP and IBM http://www.msexchange.org/tutorials/Art-Science-Sizing-Exchange2003-Part1.html 3>Should we run any form of offline defrag (on either the remote or HQ Exchange servers) before or after the mailbox moves? Run the offline defrag once the move is completed on the Source server. you can also run it on destination to make sure you reclaim maximum space. iv) I hear that mailbox moves can cause large numbers of transactions logs, not sure if this is on the source of destination mailbox server? Is enabling circular logging advised? Yes Move Mailbox will cause number of transaction logs. read below Recommendations When You Use the Move Mailbox Feature Microsoft recommends that you back up the source mailbox server before you try to move any mailboxes. Additionally, perform a full online Exchange backup of the destination server after the mailbox moves are complete. Also, consider backing up messages to .pst files; this will allow for quick recovery if individual mailboxes cannot be moved successfully. For every gigabyte of data that you move, an additional gigabyte of transaction logs is generated at the source and target server. Verify that you have sufficient free space on your transaction log drives. If you do not have sufficient free space on your transaction log drive for transaction log file generation, you could temporarily turn on circular logging on the General tab of the storage group's properties page. If you have turned on circular logging during the mailbox move, make sure that you turn circular logging off when the mailbox move is completed. If you leave circular logging turned on, you cannot restore up to the point of failure if the database has to be restored from a backup. If disk space is a concern, you may also want to consider performing incremental backups during the mailbox moves to clear log files http://support.microsoft.com/kb/821829 v) Once all mailboxes have been moved and a suitable time period passed, how do we remove the old Exchange servers from the Org? Just uninstall Exchange? You need to migrate all data's from Source server to Destination server and can decomission the old server. You can follow the below article http://support.microsoft.com/kb/822931 vi) If there are public folders on the remote Exchange servers, how can these be moved to the HQ Exch boxes? You will have to add the replicas of the PF from remote exchange servers to HQ servrs. You can use the pfmigrate utility or you can do it from ESM http://support.microsoft.com/default.aspx?scid=kb;EN-US;822895 http://www.msexchange.org/tutorials/PFMIGRATE.html vi> Make sure you backup the Source and Destination Server also destination should be higher level in terms of Service pack and hotfixes if the mailbox is huge then you can advise users to drag it to pst and then you can move across WAN which will make your job easier Vinod |CCNA|MCSE 2003 +Messaging|MCTS|ITIL V3|

Thanks...So, let's say I get information on the IOPS/mailbox, user profile and megacycles from both the source AND destination mailbox servers.Do you know how I can "merge" this information so that I can find out what the effect will be on the destination mailbox server? Also, how do I know what the acceptable limits are for the destination server?Finally, running the offline defrag, is that by running the ESEUtil command over the weekend? Any idea how I can work how long this will take?Also, there are tools like LoadSim - can this be run on the live destination mailbox server, setting it so that LoadSim is running with the extra users?Alternatively, what I could do is build a replica of the new server in the lab, run Jetstress with the settings as if the new users were on there, then install Exchange and run Loadsim with the settings for the new users...would this be a valid test?