Hi I have heard many times that Exchange 2003 has an Information Store cache that is refreshed every two hours (or when IS is restarted). Yet on countless occasions, I've made changes to someone's mailbox size limit and the change has taken about 20mins to propogate. To test, I've also changed it again, and it only took about another 20mins to propogate. We haven't made any reg keys changes to our servers to change the cache refresh time, so does anyone know why this is?

On Sat, 12-Sep-09 01:14:08 GMT, Sheen1990 wrote:>>>Hi >>I have heard many times that Exchange 2003 has an Information Store cache that is refreshed every two hours (or when IS is restarted). >>Yet on countless occasions, I've made changes to someone's mailbox size limit and the change has taken about 20mins to propogate. To test, I've also changed it again, and it only took about another 20mins to propogate. >>We haven't made any reg keys changes to our servers to change the cache refresh time, so does anyone know why this is? od of time _between_ refreshes. It's not thelength of time from the change to the refresh.On average, the time would be about one hour. It might be as short as"immediate" or as long as two hours. If you're seeing it change in 20minutes, well, that's okay!http://technet.microsoft.com/en-us/library/bb684892.aspxIf you're seeing 20 minutes (which is the MS recommended value), checkif the "Reread Logon Quotas Interval" regeistry value is present intheHKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeIS\ParametersSystemkey (it's not there by default, and if it's not there then theinterval is 7200 seconds).---Rich MatheisenMCSE+I, Exchange MVP--- Rich Matheisen MCSE+I, Exchange MVP

Hi Rich> od of time _between_ refreshes. It's not thelength of time from the change to the refreshSure...I understood that...it just seems strange that whenever I amend someone's mailbox limit, the change seems to take place fairly quickly. Of course, it could be that I am making the change just before the refresh period, but this generally happens a lot.> On average, the time would be about one hour. It might be as short as"immediate" or as long as two hours. If you're seeing it change in 20minutes, well, that's okay!Why would you say that it was an hour on average, out of interest?A question for you: the term "Information Store cache" implies that some information is cached - but what, I'm wondering? Is it *all* information relating to everyone's mailbox size limit for example? Or just the information that Exchange pulls from AD for various things? In which case, what determines why some mailbox size limits are cached and others aren't?Finally, when Sender A sends an email to Recipient B, at what time does Exchange check to see if B's mailbox size limit policy will actually allow the mail to be delivered? Whenever a mail is sent, is the size limit of the recipient always checked? And at what point?

On Sat, 12-Sep-09 22:59:07 GMT, Sheen1990 wrote:>Hi Rich>> od of time _between_ refreshes. It's not thelength of time from the change to the refresh>Sure...I understood that...it just seems strange that whenever I amend someone's mailbox limit, the change seems to take place fairly quickly. Of course, it could be that I am making the change just before the refresh period, but this generally happens a lot.e seeing it change in 20minutes, well, that's okay!>Why would you say that it was an hour on average, out of interest?Assuming you're making changes at random times, sometimes you'll makethe change closer to the end of the two-hour period, and sometimecloser to the end of the two-hour period. Since the cache refreshes ata fixed interval, the time between the change being made and the timethe IS finally sees that change will probably average about 1/2 theinterval. That's not to say your luck is better, or worse, at pickingthe time the change is made.>A question for you: the term "Information Store cache" implies that some information is cached - but what, I'm wondering? Is it *all* information relating to everyone's mailbox size limit for example? Or just the information that Exchange pulls from AD for various things? Well, that /is/ part of the information from the AD. :-)>In which case, what determines why some mailbox size limits are cached and others aren't? cached.>Finally, when Sender A sends an email to Recipient B, at what time does Exchange check to see if B's mailbox size limit policy will actually allow the mail to be delivered? That's not an easy question to answer. For mail delivered from a SMTPserver it's done at the time the IS gets the message. For mail sent byan Outlook client using RPC it's the same -- unless the mailbox that'soversized is the senders, and then it depends on what version ofOutlook, what Office SP or hotfixes ate installed, and whether theclient is working in cached or on-line mode.>Whenever a mail is sent, is the size limit of the recipient always checked? The recipient's limit is checked at the time the message is received.The sender's limit is supposed to be checked before the message leavesthe mailbox.>And at what point?---Rich MatheisenMCSE+I, Exchange MVP--- Rich Matheisen MCSE+I, Exchange MVP