Poor performance with D-Link DCS-6620G and Microsoft Windows Vista - Solved

I recently bought a D-Link DCS-6620G IP camera to replace a failed Panasonic one. I found the performance to be terrible. After running a network capture I discovered the following:

My Vista desktop would send two TCP SYN requests with ECN and CWR flags set.
The camera would resond to each of these with a TCP RST.
My Vista desktop would then send a TCP SYN request without ECN and CWR flags and the camera would then respond normally.

This problem also meant that I could not add the camera to D-Link D-ViewCam Monitor as the request to add a camera failed with an unable to connect message.

After a bit of reading, I discovered the CWR and ECN flags were being set because I had ECN enabled in my IP stack. I verified this by running:

netsh interface tcp show global
Querying active state...
TCP Global Parameters
----------------------------------------------
Receive-Side Scaling State          : enabled
Chimney Offload State               : disabled
Receive Window Auto-Tuning Level    : disabled
Add-On Congestion Control Provider  : none
ECN Capability                      : enabled
RFC 1323 Timestamps                 : disabled

Running the following, disabled the setting:

netsh interface tcp set global ecncapability=disabled
Ok.

And...

netsh interface tcp show global
Querying active state...
TCP Global Parameters
----------------------------------------------
Receive-Side Scaling State          : enabled
Chimney Offload State               : disabled
Receive Window Auto-Tuning Level    : disabled
Add-On Congestion Control Provider  : none
ECN Capability                      : disabled
RFC 1323 Timestamps                 : disabled

The camera is now working very well.

Microsoft DPM 2007 - Enable colocation of data on tape

If you have multiple storage groups with the same data retention policies, you can now colocate the data on the same tapes as long as you have installed theDPM 2007 feature pack. Most useful if you have a single drive rather than a library.

It's not settable in the GUI, but the following Powershell command turns it on:
Set-DPMGlobalProperty -DpmServer -OptimizeTapeUsage $true

More details here. 

Update Rollup 3 for Exchange Server 2007 Service Pack 1

This (KB949870), was applied by Windows Update last night, and I woke up to no incoming email. On investigation, I found that there was no smtp (25) port open, and that the Microsoft Exchange Transport hadn't started after the reboot.

I attempted to manually start the service, but no joy as it timed out after 30 seconds. I reviewed the event logs, nothing there, tried again and it worked. Did a trawl back through the event logs when the server restarted, and again nothing. There were some eventid 3001\3003 from the EvntAgnt (log file not at end) so I may be missing some logs.

The only other issue I can think of, is that this is a single server Exchange 2007 installation - I.e. The transport service is running on the same server as the mailboxes rather than on a separate edge server. I would think this receives no testing by Microsoft!

I will have to monitor this the next time I reboot. Is anyone else having this issue?

DPM 2007 Feature Pack - Out!

The feature pack that is supposed to fix quite a few issues was released on the 1st July. I seemed to have missed it even though my DPM server is subscribed to Windows Update.

Found out about it here:
http://blogs.technet.com/dpm/archive/2008/07/01/dpm-2007-rollup-update-now-available.aspx

Details from Microsoft here:
http://www.microsoft.com/downloads/details.aspx?FamilyID=e9e1fe35-b175-40a8-8378-2f306ccc9e28&DisplayLang=en
http://www.microsoft.com/downloads/details.aspx?FamilyID=ad5cd1a2-9b87-4a2c-90a2-9dbaf1024310&DisplayLang=en

Configure Server 2008 Time

I used the command:
"w32tm /config /manualpeerlist:"uk.pool.ntp.org europe.pool.ntp.org" /syncfromflags:manual /reliable:yes /update"

More details here:
http://technet2.microsoft.com/windowsserver/en/library/f3d6b66c-5fdc-4a77-a901-5efbcb4d4bb71033.mspx?mfr=true