Site Link Flooded By DAG Replication Traffic

Hi everyone,
I have a quick question regarding DAG replication. We have a DAG that stretches two sites (one site is the primary site and the other site is strictly DR). The WAN link is 150 Mbps, and we have
encoutered some issues with the network being over-saturated by bursts from the Exchange servers on the replication networks.
The manager of the Engineering team informed me of this today. Apparently this has been going on for a while, but they just discovered the cause recently. He asked about policing/rate-limiting
on traffic destined to the IP at the DR site to 100 Mbps. My understanding is that this would cause packets to drop if they go over 100 Mbps.
Now, I understand how TCP fundamentally works, and that the DAG utilizes TCP (default port 64327), so I would
like to think this wouldn't be an issue, but I wanted to open a dialog here anyway to see if anyone else has encountered anything like this, and if so, if problems arose.
As an aside, I am running Exchange 2010 SP2 (yeah, I know...hopefully going to SP3 next month). There are four total mailbox servers (three at the main site and one at the DR site). And yes,
I have collapsed my DAG networks (MAPI, Replication, Backup).
Any insight is welcome.
Thanks in advance!

Thank you, Jared and Jim.
Yes, I figured that at worst my databases at my DR site may simply fall behind a bit, but I don't think it will be by too much, as it doesn't run that high all the time.
The manager of the engineering team is scheduling up a change for Tuesday morning to effectively limit the traffic on Tuesday morning. I'll monitor it for a few days and let you guys know how it is behaving.
Thanks again and have a great weekend!

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Need to know how to calculate and allocate the server side bandwidth between two exchange sites for DAG replication

Hi All,
Please have a look in to the below mentioned environment.
primary site :SITE 1
server 1
server 2
secondary site :SITE 2
server 3
Note : All the above three servers are in single DAG .All the database are mounted on the server (server 1) which is located in the primary site (I.E SITE 1).
On that 5 databases we are having 3500 users .Based on the user designation we have allocated the mailbox size.
Query : Each and every day we are having the large no copy queue length for all the five databases to the server located in SITE 2.
Please help me out on this and also tell me is there any tool available to exactly get the required bandwidth for the exchange servers located between the active directory sites.
Thanks & Regards S.Nithyanandham

I don't know of any tool that can calculate things for you but latency is the biggest thing you have to worry about. The other issues is looking at the network gear between the 2 sites. I have seen many times were switches get maxed out if they are set to
1 GB or even ports getting maxed out and need to bonded for more throughput. Test your latency from the edge of each site then test it within to see if there is a difference.
Regardless of their geographic location relative to other DAG members, each member of the DAG must have round trip network latency no greater than 500 milliseconds between each other member.
As the round trip latency between two Mailbox servers hosting copies of a database increases, the potential for replication not being up to date also increases. Regardless of the latency of the solution, customers should validate that the networks between
all DAG members is capable of satisfying the data protection and availability goals of the deployment. Configurations with higher latency values may require special tuning of DAG, replication, and network parameters, such as increasing the number of databases
or decreasing the number of mailboxes per database, to achieve the desired goals.
Round trip latency requirements may not be the most stringent network bandwidth and latency requirement for a multi-datacenter configuration. You must evaluate the total network load, which
includes client access, Active Directory, transport, continuous replication, and other application traffic, to determine the necessary network requirements for your environment.
http://technet.microsoft.com/en-us/library/dd638104(v=exchg.150).aspx
DJ Grijalva | MCITP: EMA 2007/2010 SPA 2010 | www.persistentcerebro.com

Exchange DAG Replication Data Rate

i need some information regarding DAG replication issue. In my environment there is two mailbox server. One DC and another in DR site. The connectivity between DC and DR site is VPN. Bandwidth is one MB. But in VPN connection have ping loss. The ping loss rate
1-2%. In my environment twodatabase.
one is single and another is under the dag member. when i move mailbox from single to dag database the move rate is so slow and sometimes database going to dismount. I think its happened as because connectivity issue.
Can you please suggest the details about dag replication. I need to know that: what is dag replication
data rate? also the acceptable rate of ping loss and How much rate connectivity between DAG Heartbeat connection.
Please suggest as soon as possible.
Thanks,
Parvez

Hi Parvez,
From your description, I would like to clarify the following things:
1. It is not recommended to install Exchange server on DC.
2. The witness server is needed when there's an even number of members in the DAG. Based on your case, you need a file share witness server.
3. The DAG replication rate depends on the replication traffic.
4. By default, heartbeat frequency (subnet delay) is 1000ms for both local and remote subnets. When a node misses 5 heartbeats (subnet threshold) another nod within your DAG cluster will initiate a failover.
What's more, here are some helpful threads for your reference.
Planning for High Availability and Site Resilience
http://technet.microsoft.com/en-us/library/dd638104(v=exchg.150).aspx
Exchange 2010: Collapsing DAG Networks
http://blogs.technet.com/b/timmcmic/archive/2011/09/26/exchange-2010-collapsing-dag-networks.aspx
Hope my clarification is helpful.
Best regards,
Amy
Amy Wang
TechNet Community Support

DAG replication nic

HI
I have one exchange 2013 SP1 server holding both Mailbox and CAS roles,
I want to come up with DAG, so i am going to setup a witness server.
SRV1- Exchange 2013 SP1(MB,CAS)
SRV2 -Witness Server
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I dont have any issue configuring replication NICS but is it recommended in my scenario?
I am aware it is recommended when you want to add two members to DAG.

If you are only going to have one server then you definitely don't need any replication NICs.
I typically only use dedicated replication NICs when the following are true:
I have dedicated NICs on the physical Server that are connected to a completely separate switch (not just vLAN)
I have a dedicated WAN for replication traffic to other sites. (if DAG stretches multiple sites)
In order to get the benefits of a replication network, these need to be met (atleast in my opinion)
Are you planning on setting up a second DAG member in the future? If not, I would hold off on even setting up and configuring the DAG, since you're not going to get any of the replication benefits from the DAG. You can always configure it again later
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Active Directory Logon / Site Link Bridge Issue

Dear NC,
i have an issue with users in different Locations, to explain easyest here is a little network diagram:
So, as one can see, i have 4 Locations, one is the Headquarter.
The Target Goal is: Users in Location C must Logon with Domaincredentials from Sub.domain.tld from Location A.
Location HQ, A and B are fully routed, Location C has only a route to Location B.
Every Location has at least one writable DC with GC ans DNS Server installed.
I have the following site links:
HQ<>A
HQ<>B
A<>B
B<>C
and also a Site Link Bridge with "A<>B" and "B<>C".
Unfortunatly Users cannot logon in Location C with sub.domain.tld Domaincredentials from Location A.
Need a bit help, thx :-)
-Bernd

Hi Bernd,
I am sorry that I am a little confused here, would you please clarify what do you mean by “Users in Location C must Logon with Domaincredentials from Sub.domain.tld from Location A”?
From what I understand, you have two domains:
domain.tld and sub.domain.tld, and you want that user accounts in
sub.domain.tld (location A) can logon from domain.tld (location C), am I right?
If that is your goal, please make sure the following conditions are true:
During the logon process, specify the right domain name which is like
@sub.domain.tld.
The GC in location C is available to identify the appropriate Domain Controller for authentication process.
There is no network connectivity issues between location A and C, because after GC located a DC in location A, the logon process will take place between location A and C.
In addition, every site should have good network connectivity with at least another site to keep AD replication healthy. If there are critical errors in your HQ site, we should try
to resolve them.
Here is a related article below for your reference:
What Is the Global Catalog?
http://technet.microsoft.com/en-us/library/cc728188(v=WS.10).aspx
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Site Link Membership

Can an AD site be a member of two different site links?
Our network is a full mesh MPLS with various link speeds so I would like to control what sites replicate with each other. For example, for 4 sites with the same high speed links I was going to create a site link called Core and set replication schedule to
every 60 minutes:
When sites are part of a site link, is a full mesh topology automatically created between them?
Also, if I then wanted to force a site with a low speed link to only replicate with one of the 4 core sites I.E. Site A would i just create another site link and add the core site and the new site? If so how would costing affect this scenario if at all?

Please keep in mind that just because you can do something, doesn't mean that you should. I have managed and advised site topology for years for hundreds of companies and only
very rarely is there a need to do what you are describing. Unless there is a specific business reason for doing so, I would personally not mess with the site link costing. Keep in mind, that technology was born from the need of the day.
When AD was introduced, connection speeds were painfully slow and bandwidth needed to be managed. Admins needed to prevent replication from saturating connections needed for business apps and users. Remember, a high speed link in those days 128k
to 256k. A far cry from the performance of every MPLS network I have seen.
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Again, unless you have a specific business reason for doing what you are proposing, I would recommend leaving it alone. My 2 cents.

DAG Replication Network Isolation from MAPI

Hi,
Recently We have implemented Exchange 2010 SP2 DR setup.
We have two sites Prod and DR. We are facing some issue in DAG replication Network (Replication Adapter).
We are using 10.10.10.x for Mapi Networks and 192.168.1.x for Replication Network for Prod and 10.11.10.x for MAPI and 192.168.2.x for Replications.
As per Microsoft recommended, We configured replication adapters and added static routes for Replication Network.
We understand, Replicarion adapter is used for DAG Replication (Log Shipping and Seeding) and configured forewall to allow tonly DAG port 64327 for replication Vlans between sites.
Now, When we check the replication network hit in firewall. Its still using MAPI Network (MAPI Nic) to communication with DR sites. Replication Nics is not working properly.
Please let me know, How to isolate the MAPI and Replication Networks. Do we need configure Replication Port in DAG properties.
How to check whether Replication Network is working between the sites.
Regards
M

My Problem is, While seeding is happening between Primary Site to DR Site. Connections are going only via MAPI Networks. It is not using Replication Netowork. I have added the static route in all the prod and DR Mailbox Servers. But I have not
configured Replication Port in DAG properties. And also, I allowed only Port 64327 for Replication Vlan in both Primary and DR. Please let me know if you have any solutions. Regards M
That's expected if you are just using the EMC, or using standard options via EMS
What happens if you use
http://technet.microsoft.com/en-us/library/dd335201(v=exchg.141).aspx
Update-MailboxDatabaseCopy -Network
and
http://technet.microsoft.com/en-us/library/dd335158.aspx
Managing Mailbox Database Copies
To specify the networks you want to use for seeding, use the Network parameter when running the
Update-MailboxDatabaseCopy cmdlet and specify the DAG networks that you want to use. If you don't use the
Network parameter, the system uses the following default behavior for selecting a network to use for the seeding operation:
If the source server and target server are on the same subnet and a replication network has been configured that includes the subnet, the replication network will be used.
If the source server and target server are on different subnets, even if a replication network that contains those subnets has been configured, the client (MAPI) network will be used for seeding.
If the source server and target server are in different datacenters, the client (MAPI) network will be used for seeding.
Cheers,
Rhoderick
Microsoft Premier Field Engineer, Exchange
Blog:
http://blogs.technet.com/rmilne Twitter:
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SCCM 2012 - Incoming Message queue status showing 104074 and Site link failed from CAS to Primary

HI
dbo.configmgrDRSQueue is automatically stopping and when we try to enable it it is slowiy decreasing by 4- 5. we would like to clear the queue in one shot to re-initiate the sync between the CAS to affect Primary site server so please help on this.

Hi,
Have you tried to use Replication Link Analyzer to repair replication issues? Please check the article below.
Replication Link Analyzer in Configuration Manager 2012
https://gallery.technet.microsoft.com/Replication-Link-Analyzer-cdbefc49
Best Regards,
Joyce
Please remember to mark the replies as answers if they help and unmark them if they provide no help. If you have feedback for TechNet Subscriber Support, contact [email protected]

What is a Site Link Cost?

I'm a Student trying to get MCITP. Please tell me when i am configuring Replication between sites, What is the site link cost means? What can i do from that? please tell me
Regards,
Ashane Deshapriya.
Ashane Deshapriya ( MCP )

Hi Ashane Deshapriya,
The cost setting on a site link object determines the likelihood that replication occurs over a particular route between two site. Relication routes with the lowest cumulative cost are preferred. You can use this procedure to configure replication cost on
the site link object in Active Directory Domain Services (AD DS). When you create or modify site links, use the site link object properties to configure the relative cost of using the site link.
For your information, please refer to the following articles to get more help:
Configure the Site Link Cost to Establish a Priority for Replication Routing
Configure site link cost
Regards,
Lany Zhang

Are Secondary AD Site links actually required?

Consider this: You have three AD sites; A, B, and C.
All three have independent network connections to each other, and all three have multiple domain controllers.
Connectivity and reliability at Site B is best, so you decide you use that as the hub of your replication topology. You configure an A-B site link, and a B-C site link.
Question: Do you actually need an A-C site link in case connectivity to B goes down? Or will the KCC attempt to make that connection on its own, based on the existing links?

No A-C site link needed if you have not disabled "Bridge all site links" (BASL). By default, BASL is enabled.
See
http://technet.microsoft.com/en-us/library/cc756899(v=WS.10).aspx , Site link transitivity:
"By default all site links are transitive, or "bridged." When site links are bridged and the schedules overlap, the KCC creates replication connections that determine domain controller replication partners between sites, where the sites are
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When I first open Firefox it is fine but if I open a second tab to search another site I get a white screen and have to continually click 'back', click the site link, white screen, back, click the link, white screen and so on.

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This can also be a problem with the files [http://kb.mozillazine.org/sessionstore.js sessionstore.js] and sessionstore.bak in the [http://kb.mozillazine.org/Profile_folder_-_Firefox Profile Folder]
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I have a SharePoint Site Collection under my main
Web Application: mywebapp:80.
I had to extend this to an Intranet zone
Web Application: mywebapp:101.
I am able to open my Site Collection from either address. The authentication protocols for both are the same.
When provisioning the User Profile Service and configuring
My Site, the
My Site Host Location must be supplied, in this case: http://mywebapp:80/personal/mysite
I housed my My Site Host under the same Web Application as my
Site Collection.
When accessing My Site for any given user from mywebapp:80, all the links of user photos point to that same
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2.) What are possible implementation alternatives for cases like this when I need to use
My Site under 1
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multiple host names?

Hi Noel,
perhaps this thread is similar with your question:
http://social.technet.microsoft.com/Forums/sharepoint/en-US/d3010532-ae20-4eda-8f58-359f77d17e1e/user-profile-pictures-pointing-to-old-mysitehost?forum=sharepointadminprevious
any way, for your 2 questions,
perhaps you can give us more details about the scenario?
as i know,
mysite able to adjust, but you may need to configure the the host of the mysite, for example:
1. to the User Profile Service Application (UPA) and changed the MySite URL, few sites show the new URL and few show the old one.
2. to Central Admin and found there may 2-UPAs created.
3. changed the MySite settings on both the UPAs, created Managed Paths wherever necessary and then changed associations of all web applications to one of the main UPA
for configuring the multiple host, you may check with your IIS, and add the bindings,
http://forums.iis.net/t/1189870.aspx
http://stackoverflow.com/questions/14232892/multiple-sites-under-the-same-hostname-possible
Regards,
Aries
Microsoft Online Community Support
Please remember to click “Mark as Answer” on the post that helps you, and to click “Unmark as Answer” if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

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This thread should be helpful - http://forums.adobe.com/message/5147694.
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Run into an issue where the 'Sharepoint Sites' link won't create in the user profile \ favourites when using the Connect to Office function from Libraries.
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Hi all,
Run into an issue where the 'Sharepoint Sites' link won't create in the user profile \ favourites when using the Connect to Office function from Libraries.
This is an on premise Sharepoint 2013 installation. Users connect to different Terminal Servers to access Office 2010 applications.
Issue only affects new users.
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The user regkey HKCU\Software\AppDataLow\Microsoft\Office\15.0\Common\Portal gets created. Subsequently clicking Connect to Office seems to fail. I suspect this is because it knows the Office installation is only 2010 & tries to create the Publishing
time stamp key in HKCU\Software\AppDataLow\Microsoft\Office\14.0\Common\Portal but this path does not exist.
Logging the user into a Terminal Server that only has Office 2010 installed generates the correct Regkeys & the Sharepoint Sites link creates successfully in the user profile.
Has anyone else seen this or know of a fix to get around the Office2013 being used as the default regkey path?
Cheers

Need script to automate creation of AD sites,subnets and site links

Hello,
I have a requirement to create hundreds of sites and thousands of subnets in AD and also site links. I have an excel file with the details.
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BR,

Hi AD-learner,
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www.jijitechnologies.com

Site Link Flooded By DAG Replication Traffic

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