none
Calendar Availability and CAS-CAS proxying

    Question

  • At the moment I am having an issue where one users active at one site cannot see the calendar availability of users at the second site. CAS01 is at our primary site, and CAS02 is at our secondary. Users active at the same site can see each other's calendars in outlook 2010, but it does not work cross-site.

    Is this an issue with availability URLs? I have checked these and cannot find anything wrong. What about firewall rules? Do i need specific rules on our firewalls to allow the traffic?

    Tuesday, July 30, 2013 4:26 PM

Answers

All replies

  • Are there firewalls between the Exchange Servers? Thats a big no-no unless the rules are set to allow ANY/ANY. 
    Typically, when free/busy fails like this, the event logs on the CAS show some useful errors.

    http://blogs.technet.com/b/exchange/archive/2013/02/18/exchange-firewalls-and-support-oh-my.aspx

    Starting with Exchange Server 2007 and current as of Exchange Server 2013, having network devices blocking ports/protocols between Exchange servers within a single organization or between Exchange servers and domain controllers in an organization is not supported. A network device may sit in the communication path between the servers, but a rule allowing “ANY/ANY” port and protocol communication must be in place allowing free communication between Exchange servers as well as between Exchange servers and domain controllers


    Twitter!: Please Note: My Posts are provided “AS IS” without warranty of any kind, either expressed or implied.

    Tuesday, July 30, 2013 6:37 PM
  • Indeed - pesky firewalls :)

    Can you tell us what the EWS URLs are set to please in both of these sites. 

    Paste this in here, change the name to contoso.com but leave the rest -as-is

    Get-WebServicesVirtualDirectory | Select Name, *URL* | FL

    Get-WebServicesVirtualDirectory | Select Name, *URL* | FL


    Cheers,

    Rhoderick

    Microsoft Senior Exchange PFE

    Blog: http://blogs.technet.com/rmilne  Twitter:   LinkedIn:   Facebook:   XING:

    Note: Posts are provided “AS IS” without warranty of any kind, either expressed or implied, including but not limited to the implied warranties of merchantability and/or fitness for a particular purpose.

    Wednesday, July 31, 2013 12:48 AM
  • Name                 : EWS (Default Web Site)
    InternalNLBBypassUrl : https://cas10.contoso.com/ews/exchange.asmx
    InternalUrl          : https://autodiscover.contoso.com/EWS/Exchange.asmx
    ExternalUrl          :

    Name                 : EWS (Default Web Site)
    InternalNLBBypassUrl : https://cas11.contoso.com/ews/exchange.asmx
    InternalUrl          : https://autodiscover.contoso.com/EWS/Exchange.asmx
    ExternalUrl          :

    Name                 : EWS (Default Web Site)
    InternalNLBBypassUrl : https://cas2.contoso.com/ews/exchange.asmx
    InternalUrl          : https://autodiscover.contoso.com/EWS/Exchange.asmx
    ExternalUrl          : https://drwebmail.contoso.com/ews/exchange.asmx

    Cas10 and Cas11 are at the priamry site, and Cas2 is at the DR site.

    I'll check on the firewalls in the way and get back to you on that.

    Wednesday, July 31, 2013 9:33 AM
  • Please also check the firewall, but the above needs changing.

    Why is the same namespace used in two sites?  And why is it autodiscover?  I know that it's only a name, but still :)

    CAS in site 1 will look to hit CAS in Site two by using the internalURL.  How can it get there as where does that resolve to - see where I'm going with this...

    Also why is ExternalURL set in Site 2, but not in site1? 

    Get a *LARGE* mug of coffee and read through this a couple of times

    http://technet.microsoft.com/en-us/library/bb310763.aspx


    Cheers,

    Rhoderick

    Microsoft Senior Exchange PFE

    Blog: http://blogs.technet.com/rmilne  Twitter:   LinkedIn:   Facebook:   XING:

    Note: Posts are provided “AS IS” without warranty of any kind, either expressed or implied, including but not limited to the implied warranties of merchantability and/or fitness for a particular purpose.

    Wednesday, July 31, 2013 11:44 AM
  • Apologies if this is strange. This is an environment that I have inherited.

    It's kind of a stretched site. They are in different phyiscal locations but part of the same domain.

    Could  you provide an example of what it should look like?

    Wednesday, July 31, 2013 11:49 AM
  • Is it really streached?  i.e. are there two AD sites or just one?

    if it is a single AD site, then all CAS *MUST* be set consistently in the same AD site. 

    This is all related to CAS Namespace planning.    In terms of what it should be, well it's the consultants answer: "It depends".  One example would be (assuming load balancers) described in the article above.  in site1 set the URLs to be mail.contoso.com and in site2 set the URLs to be mail2.contoso.com.  But read through the article please as you then need to know when and why you would set external URLs on the second site and what namespace should be used.  Apologies, but there are soooooo many IFs.....

    

    Cheers,

    Rhoderick

    Microsoft Senior Exchange PFE

    Blog: http://blogs.technet.com/rmilne  Twitter:   LinkedIn:   Facebook:   XING:

    Note: Posts are provided “AS IS” without warranty of any kind, either expressed or implied, including but not limited to the implied warranties of merchantability and/or fitness for a particular purpose.

    Wednesday, July 31, 2013 11:58 AM
  • http://blogs.technet.com/b/exchange/archive/2010/11/22/3411576.aspx

    http://technet.microsoft.com/en-us/library/dd351198.aspx

    .

    .

    This is an example, don't take it as gospel, 

    https://www.facebook.com/photo.php?fbid=529823497049935&set=pb.455588957806723.-2207520000.1375271977.&type=1&theater 

    Hit the photo viewer button thingy to make it readable.


    Cheers,

    Rhoderick

    Microsoft Senior Exchange PFE

    Blog: http://blogs.technet.com/rmilne  Twitter:   LinkedIn:   Facebook:   XING:

    Note: Posts are provided “AS IS” without warranty of any kind, either expressed or implied, including but not limited to the implied warranties of merchantability and/or fitness for a particular purpose.

    Wednesday, July 31, 2013 12:01 PM
  • Hello,

    Per your situation, the Availability service cross sites performs as: when users in the primary site accessing the mailbox in DR site, CAS2 proxies to a CAS server in the primary site by using the FQDN specified by the InternalURL property of the /EWS virtual directory, vice versa. For your reference: http://technet.microsoft.com/en-us/library/bb310763(v=exchg.141).aspx .

    The appropriate values for the InternalUrl properties of all CAS servers in organization should be https://fullyqualifiedcomputername/EWS/Exchange.asmx .

    Please use the command below with EMS to correct the InternalURL of all your CAS servers:

    Set-WebServicesVirtualDirectory –Identity “EWS <Default Web Site>” – InternalUrl:https://fullyqualifiedcomputername/EWS/Exchange.asmx

    Best Regards

    Wednesday, July 31, 2013 1:30 PM
  • Hello,

    Per your situation, the Availability service cross sites performs as: when users in the primary site accessing the mailbox in DR site, CAS2 proxies to a CAS server in the primary site by using the FQDN specified by the InternalURL property of the /EWS virtual directory, vice versa. For your reference: http://technet.microsoft.com/en-us/library/bb310763(v=exchg.141).aspx .

    The appropriate values for the InternalUrl properties of all CAS servers in organization should be https://fullyqualifiedcomputername/EWS/Exchange.asmx .

    Please use the command below with EMS to correct the InternalURL of all your CAS servers:

    Set-WebServicesVirtualDirectory –Identity “EWS <Default Web Site>” – InternalUrl:https://fullyqualifiedcomputername/EWS/Exchange.asmx

    Best Regards

    Does that mean that they should be set up as follows:

    Name                 : EWS (Default Web Site)
    InternalNLBBypassUrl : https://cas10.contoso.com/ews/exchange.asmx
    InternalUrl          : https://cas10.contoso.com/ews/exchange.asmx
    ExternalUrl          :

    Name                 : EWS (Default Web Site)
    InternalNLBBypassUrl : https://cas11.contoso.com/ews/exchange.asmx
    InternalUrl          : https://cas11.contoso.com/ews/exchange.asmx
    ExternalUrl          :

    Name                 : EWS (Default Web Site)
    InternalNLBBypassUrl : https://cas2.contoso.com/ews/exchange.asmx
    InternalUrl          : https://cas2.contoso.com/ews/exchange.asmx
    ExternalUrl          :

    Also, I noticed in http://technet.microsoft.com/en-us/library/dd351198.aspx tha:

    "The ExternalURL property on each virtual directory in a site that contains user mailboxes must be set to $null."

    Does that mean that the I should remove this for CAS03. Would that help?

    Also I checked and there are 2 AD sites, with 10 and 11 in the primary and 02 in the secondary site


    • Edited by snorri788 Wednesday, July 31, 2013 2:49 PM
    Wednesday, July 31, 2013 2:39 PM
  • What context what the ExternalURL set to be $Null?  I want to make sure I'm reading the same section.

    And coming back to what to set the values to, server FQDN is the default of if the box.  BUT - that is not necessarily the correct value, do you have a load balancer for example?  So we can't have a blanket statement as the presence/absence of the LB is unknown.

    You will have to get rid of the autodiscover silliness though :)


    Cheers,

    Rhoderick

    Microsoft Senior Exchange PFE

    Blog: http://blogs.technet.com/rmilne  Twitter:   LinkedIn:   Facebook:   XING:

    Note: Posts are provided “AS IS” without warranty of any kind, either expressed or implied, including but not limited to the implied warranties of merchantability and/or fitness for a particular purpose.

    Thursday, August 01, 2013 1:16 AM
  • Hello,

    Thank you for reply. The ExternalURL setting should be various between the Internet-facing CAS server and non-Internet-facing one.

    The ExternalURL settings for an Internet-facing Client Access server should be https://mail.contoso.com/*, and * corresponds to OWA,EWS,ECP, etc. However, the alternative one should be set to $null as you said. For your convenience: http://technet.microsoft.com/en-us/library/bb310763(v=exchg.141).aspx .

    And your externalurl being set as “https://drwebmail.contoso.com/ews/exchange.asmx” is ok, so leave it alone.

    Any other question, please be free to let me know.

    Thanks
    Thursday, August 01, 2013 6:40 AM
  • The ExternalURL to $null is referenced in the Single Namespace with Multiple Sites section. We run 2 internet facing AD sites. The main one has 2 CAS, CAS 10 and 11 and the secondary site has 1 CAS; CAS02.

    To my knowledge there is no other load balancer present, apart from that the CAS's at the main site are in a CAS Array.

    Thursday, August 01, 2013 10:42 AM
  • The OWA url for the main site is https://webmail.contoso.com/owa. Does that mean that the external URL should be https://webmail.contoso.com/EWS? What about the internal URLs?

    Thursday, August 01, 2013 10:43 AM
  • A

    The ExternalURL to $null is referenced in the Single Namespace with Multiple Sites section. We run 2 internet facing AD sites. The main one has 2 CAS, CAS 10 and 11 and the secondary site has 1 CAS; CAS02.

    To my knowledge there is no other load balancer present, apart from that the CAS's at the main site are in a CAS Array.

    A CAS array itself is not a load balancing mechanism. Is there a separate load balancer in the main site?


    Cheers,

    Rhoderick

    Microsoft Senior Exchange PFE

    Blog: http://blogs.technet.com/rmilne  Twitter:   LinkedIn:   Facebook:   XING:

    Note: Posts are provided “AS IS” without warranty of any kind, either expressed or implied, including but not limited to the implied warranties of merchantability and/or fitness for a particular purpose.

    Thursday, August 01, 2013 11:59 AM
  • Hello,

    Thank you for reply. The ExternalURL setting should be various between the Internet-facing CAS server and non-Internet-facing one.

    The ExternalURL settings for an Internet-facing Client Access server should be https://mail.contoso.com/*, and * corresponds to OWA,EWS,ECP, etc. However, the alternative one should be set to $null as you said. For your con

    venience: http://technet.microsoft.com/en-us/library/bb310763(v=exchg.141).aspx .

    And your externalurl being set as “https://drwebmail.contoso.com/ews/exchange.asmx” is ok, so leave it alone.

    Any other question, please be free to let me know.

    Thanks

    I have to ask. You say to set EWS ExternalUrl to $null, and then say its ik to leave it populated. Which is it?

    Cheers,

    Rhoderick

    Microsoft Senior Exchange PFE

    Blog: http://blogs.technet.com/rmilne  Twitter:   LinkedIn:   Facebook:   XING:

    Note: Posts are provided “AS IS” without warranty of any kind, either expressed or implied, including but not limited to the implied warranties of merchantability and/or fitness for a particular purpose.

    Thursday, August 01, 2013 12:02 PM
  • For internal URLs -- ideally they point to a load balancer as mentioned in the proxy and redirection article.  this is a sample to give you an idea...exchange 2010 multi site URLs

    Cheers,

    Rhoderick

    Microsoft Senior Exchange PFE

    Blog: http://blogs.technet.com/rmilne  Twitter:   LinkedIn:   Facebook:   XING:

    Note: Posts are provided “AS IS” without warranty of any kind, either expressed or implied, including but not limited to the implied warranties of merchantability and/or fitness for a particular purpose.

    Thursday, August 01, 2013 12:31 PM
  • We don't have any other load balancers in the environment.

    I'm starting to get confused here. What should my URLs be, and why is the availability service failing?

    Thursday, August 01, 2013 2:22 PM
  • Change internal URLs back to the default which is server fqdn. Its failing as you have it set to autodiscover.domain.com in both sites. When DNS resolves that name, how can it possibly refer to both a local and remote Server? Change back to defaults, replicate ad between sites then run iisreset on all CAS.

    But as I mentioned, you have to design This multi site deployment correctly, or your predecessor, and cas namespace planning is one aspect. Differernt customers do different things if they want active/active, active/passive, single external namespace or Multiple external namespaces. Yes this is complicated and it needs time and detail.


    Cheers,

    Rhoderick

    Microsoft Senior Exchange PFE

    Blog: http://blogs.technet.com/rmilne  Twitter:   LinkedIn:   Facebook:   XING:

    Note: Posts are provided “AS IS” without warranty of any kind, either expressed or implied, including but not limited to the implied warranties of merchantability and/or fitness for a particular purpose.

    Thursday, August 01, 2013 2:51 PM
  • http://blogs.technet.com/b/exchange/archive/2012/03/23/demystifying-the-cas-array-object-part-1.aspx

    And for casarray not doing load balancing read this pls


    Cheers,

    Rhoderick

    Microsoft Senior Exchange PFE

    Blog: http://blogs.technet.com/rmilne  Twitter:   LinkedIn:   Facebook:   XING:

    Note: Posts are provided “AS IS” without warranty of any kind, either expressed or implied, including but not limited to the implied warranties of merchantability and/or fitness for a particular purpose.

    Thursday, August 01, 2013 2:53 PM
  • We don't have any other load balancers in the environment.

    I'm starting to get confused here. What should my URLs be, and why is the availability service failing?


    Hello,

    Thank you for reply. I may not make myself clear, please set as follows:

    Name                 : EWS (Default Web Site)
    InternalNLBBypassUrl : https://cas10.contoso.com/ews/exchange.asmx
    InternalUrl          : https://cas10.contoso.com/ews/exchange.asmx
    ExternalUrl          :
    Name                 : EWS (Default Web Site)
    InternalNLBBypassUrl : https://cas11.contoso.com/ews/exchange.asmx
    InternalUrl          : https://cas11.contoso.com/ews/exchange.asmx
    ExternalUrl          :

    Name                 : EWS (Default Web Site)
    InternalNLBBypassUrl : https://cas2.contoso.com/ews/exchange.asmx
    InternalUrl          : https://cas2.contoso.com/ews/exchange.asmx
    ExternalUrl          : https://drwebmail.contoso.com/ews/exchange.asmx

    Thanks
    Friday, August 02, 2013 2:00 AM
  • Apologies for partaking in some minor threadromancy here, but there are some issues after affecting this change to our Web Services URLs.

    Mainly the issue revolves around certificates and outlook. After doing this change I get a certificate warning every time Outlook 2010 is opened. What else do I need to change here to get this to work. My internal certificates?

    Monday, August 26, 2013 9:42 AM