Friday, February 20, 2009

WHY MY BLACKBERRY USERS COMPLAINING?



This question has been asked several times, why am I having trouble with my BES users and how am I going to troubleshoot this issue?

download .doc version here

Before we start doing anything

  • RIM recommends centralized architecture when it is possible and all the times.
  • MAPI is a heavy protocol and it is not designed for WAN connections
  • RIM also advices to make sure the latency is less than <35 millisecond between the black Berry server and the mailbox server.

So if you did not fallow the best practices and you have mail server in location A and BES server in location B, you know what is causing the issue, you implementation is WRONG!!! (-:

Okay I hear you did not design this, the person who designed the BES architecture took off the company long time ago and you have to live with it. How are you going to explain what is going on wrong to your manager?

Step 1

The MAPI subsystem is being used by BES agents. When a user added to BES server BES uses BB AGENTS (MAPI APIs) to locate the user mailbox on the exchange server and create hidden folders as fallows. The native Exchange APIs being used to create folders below, there is no DLL in the user mailbox unlike SQL database.

  • BlackBerryHandheldinfo
    • BlackBerryCalSyncState
    • BlackBerryICSState
    • BlackBerryMsgOnDeviceSearchFolder
    • BlackBerryRefIDSearchFolder1_7

If you wish to see the folders with your own eyes download MFCMapi and fallow the steps below

  • Download mfcmapi and double click on it ( I assume you are doing this from your workstation where outlook has already been installed and configured for you or others)
  • Click "ok" to continue
  • Click Session "Logon and Display Store Table"
  • Chose your profile click "ok"
  • Make a right click and select "open Store"
  • Expend "Root Container"
  • Expend folder called "BlackBerryHandheldInfo" folder to see all the folders associating with user mailbox

Step 2

After BES folders have been created within the user mailbox BES begins to monitor user mailbox by using AGENTS= MAPI , ***these folders are located under root container on your mailbox***. BES agents keeps track of information status within the user mailbox such as read/unread/moved/deleted/reconciled] and calendar state.

BES agents also copies every single message and pulls back to your BES server to be travel on port 3100 to RIM facilities & Servers on Canada and lets ISP wireless provider to grap the message and place onto your BB handheld device.

So if your user is telling you I received e-mail from my friend to my Black berry and never received on my outlook, you know right of the bat , this is impossible (-:

Now here is first and big problem, MAPI does not like to run in the network where MS is >35 millisecond. So here is the formula to calculate the latency

  • MAPI needs to be <35Milsec , issue extended ping to find out the averaged ping packet
  • If averaged ping packet is 345 the formula is applied as fallows
    • Link Speed = 16000 / (average ping for 2048 byte packet)
    • 16000 / divide into 345 = 46Kbpc
    • The link would be considered slow, the trash hold round-trip time for a fast link (default = 500 Kbps) is 32 ms.
    • If you remember on 100meg LAN connection the Speed would be less than 1ms, if you perform the same test within the LAN
    • From Experience if these ms go above >200 and up, good luck even opening up Outlook. The bandwidth is the culprit and client must get better connection.

Conclusion:

  • RIM recommends centralized architecture when it is possible
  • RIM also advices to make sure the latency is less than 35 millisecond between the black Berry server and the mailbox server.
  • BlackBerry users cause additional overhead that affect the database IOPS of a server.
  • Many customers see a two to four fold increase in database disk I/O.


    If you like to read more about it


    http://smtp25.blogspot.com/2007/10/blackberry-cause-additional-overhead-on.html


    Oz Ozugurlu MVP (Exchange)


    MCITP (EMA), MCITP (EA) MCITP (SA)

    MCSE (M+, S+) MCDST,

    Security+, Server +, Project+

    Blog: smtp25.blogspot.com

    Blog: telnet25.wordpress.com

2 comments:

Salvatiry Carlino said...

It's completely normal when you experience problems with your BES. It just depends on your location, and if you've installed pretty much every application on your BB. The best thing you can do to improve the performance of your BB, is to get a better server or uninstall some applications.

Hill said...

Great and simple post you shared. Blackberry has such a mythology about it, but it really is just making a common sense! Thanks for pointing that in your post.



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