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mfinni
Asked: 2015-01-31 14:46:26 +0800 CST

Query for existing Exchange Web Service subscription?

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We have a problem with Cisco Unity and Exchange 2010. We've done packet capture and have determined that EWS is not sending <t:ModifiedEvent> notifications to the Unity server for some users.

Is there a way of querying Exchange to list what EWS subscriptions it's pushing or streaming?

exchange-2010

1 Answers

  1. Best Answer

    Will rewrite from my comment correctly.

    In EWS. No. The EWS API just support to create a subscription or with the GetEvent to retrive the information, but you need to provide the watermark and the subscriptionID for such request or the request fail. As like I told earlier in my comment, in EWS you connect with a user credential, thus the subscription is binded to that account unless the account can impersonate. The application that use EWS for getting such notification is indirectly responsible to keep the subscriptionid and watermark, and it havea timeout in Exchange in case the application close without closing the subscriptions.

    Reference there

    • The SubscriptionID of the request is confirmed to be a valid subscription that is hosted on the Client Access server. If it is not, the GetEvents call fails.
    • The SMTP address of the authenticated user for the request is compared to the SMTP address of the user who created the subscription. If they do not match, the GetEvents request fails.
    • The subscription queue is queried for events that are waiting to be sent to the client. If the queue is not empty, the first 50 events from the queue are pulled from the queue and encoded into a notification.
    • If no events are found in the queue, a StatusEvent is generated and encoded into a notification response.
    • The notification response is returned to the client.
    • The events that are included in the notification are removed from the subscription queue and the Client Access server local last watermark for the subscription is set to the watermark of the last event that is returned.
    • The timeout timer for the subscription is reset.

    In exchange powershell, not yet. You can only see throttling policy around subcriptions.

    In the eventlog, maybe, worth a try. You can see some event by default, like;

    Event Type: Warning Event Source: MSExchange Web Services Event Category: Core Event ID: 5 Date: 2009-02-27 Time: 19:57:49 User: N/A Computer: MY-SERVER Description: Unable to send a notification for subscription HQBhd3N0b3NydjA1LmFjYWRlbWljd29yay5sb2NhbBAAAACykwfyGuuJSIrp5cV7B8Ie. Will retry. Get from there

    That lead me to suggest you to try to set the eventloglevel on other level to see if you can find more usefull information. With powershell command like; "Set-EventLogLevel “MSEXchange Web Services\Core” –Level High"

    MSExchange Web Services\Core or in 2013 they have added too: MSExchangeSubmission\MSExchangeSubmission

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