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Showing posts from March, 2015

Throttling Hyper-V Replication Traffic

We have a client with two physical locations and a 100 Mbps link between them. For disaster recovery purposes, we are using Hyper-V replication between the two sites. Recently we made a disk change to one of the VMs that forced us to delete and recreate replication for one of the VMs. Unfortunately it was the VM with 650 GB of data. Because replicating that amount of data in the best case will take about 13 hours over the WAN link, we need to control the replication and prevent it from interfering with normal business. Hyper-V does not have any built in functionality to control bandwidth for replication traffic. Fortunately Windows Server 2012 R2 has quality of service (QoS) functionality built into the operating system. In my case, the receiving server is using port 443 to receive the data. On the source server, vmms.exe is replicating the data to the destination server. I created policy that limited traffic to 50 Mbps from vmms.exe to port 443 with the following command: New-NetQosPo

Exchange 2013 Is Filling My C: Drive

So, Exchange 2013 does a few things differently than previous versions of Exchange. If you are not careful about how you allocate your disk space, you'll end up constantly wondering why the C: drive is filling up. And if your monitoring isn't up to snuff, you'll notice C: drive is filling up because mail flow almost stops due to back pressure. If you are using direct attached storage for your C: drive as Microsoft suggests, then you likely have a fairly large C: drive. Something like 300GB or more. If you have a C: drive that large you're likely OK and don't need to worry about it. On the other hand, if you have your Exchange server using a SAN and you tried to keep your C: drive to 80GB because that SAN space is expensive, you will have issues. There are three common things can use up the C: drive: Internet Information Services (IIS) logs Exchange Server diagnostic logs Transport queues IIS Logs Exchange Server has a variety of web-based services such as Outlook We

Set a New Internal Transport Certificate

Normally, when we configure clients running Exchange 2013 with a valid certificate for web services, we also apply it to SMTP. This allows opportunistic TLS to be performed and secure email delivery. When you apply the certificate, it will ask: Overwrite the existing default SMTP certificate? We normally say yes and our valid/trusted certificate is configured as the "internal transport certificate". This is all good. Recently the certificate on an Exchange 2013 server was replaced and when the new certificate was applied, it was not configured as the default/internal transport certificate. This caused the following error when I attempted to remove the expired certificate:  A special Rpc error occurs on server XXXXXXX: The internal transport certificate cannot be removed because that would cause the Microsoft Exchange Transport service to stop. To replace the internal transport certificate, create a new certificate. The new certificate will automatically become the internal tr

High Disk Utilization on SBS 2011

High disk activity on SBS 2008 and SBS 2011 is an ongoing concern for our clients. Just yesterday, we had an SBS 2011 server with so much disk activity that it slowed down the Hyper-V host so that all VMs were not performing properly. To diagnose this issue, use Resource Monitor to view the Queue Length. When there is a problem the Queue length for a drive will be high and sustained. The % Active Time will also be high. These indicate that the disk is busy and has a backlog of work to perform. It's important to note that the actual disk I/O may not be that high. In our case, the Disk I/O was less than 10 MBps which is far less than the disk system is capable of. The Disk I/O can be low but the disks busy when many small operations are performed. The fix for this is almost always recreating the SBS Monitoring database. The SBS Monitoring database grows over time and eventually becomes a performance issue. We don't use any historical information in that database. So, removing it

Office 365 Deleted Item Retention

Microsoft recently announced that deleted item retention in Office 365 will now default to indefinite. Until now, items in Deleted Items were removed after 30 days. This was announced here: http://blogs.office.com/2015/02/20/extended-email-retention-deleted-items-office-365/ Microsoft indicates in this blog that it's implemented based on ignoring Deleted Items if the policy name is the default name. I just migrated my mailbox to O365 and it appears that while items directly in Deleted Items are no longer removed after 30 days, items in subfolders are still removed. In my newly migrated mailbox I had some old subfolders that had been removed and were in Deleted Items. There is no longer any content in those folders but all of the items directly in Deleted Items have been retained.

ActiveSync Settings for Office 365

Our office email system has been running in hybrid mode for the last year or so. That was mostly for us to do testing related to client projects. This weekend we moved all of our accounts to Office 365. Autodiscover worked well for the Outlook clients, but not for the phones. For our Android phones we removed the existing account and readded the account. My Galaxy S4 did not do failover in autodiscover properly from our on-premises autodiscover to Office 365 autodiscover. So, I ended up manually configuring the ActiveSync account. If you are manually configuring the ActiveSync account for Office 365, the server name is: outlook.office365.com