1While working on my most recent Hyper-V Replica PowerShell script when attempting to reverse replication from a source Hyper-V host to the a target host using Certificate authentication I was getting the error message…

Hyper-V failed to establish a connection with the Replica server ‘<target hostname>’ on port ‘443’. Error: The connection with the server was terminated abnormally (0x00002EFE).

As it turns out I had recently deleted and created a new certificate for the target host and as such there was no certificate listed in Hyper-V Settings > Replication Configuration. The fix was to set the replacement certificate in the box provided. See the screenshots below for a little more…

Having recently purchased a Dell T430 tower server which we will be using for backup and Hyper-V replica I thought I’d share some photos of what the castors (an option in place of either the rack mounting kit or the floor stand feet) look like!

The castor assembly comes in a separate box to the server and only takes a minute or two to install; I perhaps was expecting slightly larger wheels however they do a good job all the same on hard floors.

The screenshot above shows a portion of the sensor in its default form; in this post I’m going to show how to…

  • Remove the red ‘downtime’ line from the bottom of the chart
  • Set maximum and minimum values of the graph to display 0 to 100%
  • Set the gauge to display its value in GByte instead of MByte

Red Downtime line

Pure aesthetics with this tweak – the memory sensor isn’t something that I would expect to ever encounter downtime (if there server were offline then the PING sensor would pause the memory sensor automatically). The only real application for the downtime sensor would be if WMI wasn’t responding.

Max and Min

PRTG will automatically set the scale for your graphs but I prefer to see the full range of 0 – 100%; this tweak makes that possible.

GByte instead of MByte

When working with servers with small amounts of RAM (lets say 4GB and less) it is typically going to work out best to view free RAM as MBytes but when working with Hyper-V hosts (48GB and 96GB in my case) GBytes are a much better value to work with.

The end result…

Its been a day or so since buying a Microsoft Band 2 (took a while to find a high street shop that had one to try on in the first place!) and its proving rather useful to me as a person who rarely has his phone turned on loud and really never notices the little vibrations from it. My most recent application of Band 2 has been using it to receive push notifications from PRTG via my Windows Phone.

In all truth if you already have push notifications setup then you are probably already getting the notifications however if you are not keep reading to find out where to check for the right settings…

On the Microsoft Health App/Band Tiles

On the PRTG App

On your PRTG Console

On your Notification Settings

WP_20151112_10_34_28_RawAs part of an ongoing project to improve the room today we’ve been installing a set of rails for a pair of Dell PowerEdge T430 servers. You may have noticed the ‘T’ in the T430 to indicate they are tower servers but Dell provides a 5U rack conversion kit which is pretty easy to install.

One small question came up while putting the rails in – ‘Where do I mount the rails in relation to the 5U of space in the rack?’ to answer that question the bottom of the rails go at the bottom of the 5Us of space. Hopefully the image to the right illustrates this better!

This is how your folder should look once updated

This is how your folder should look once updated

Following from Automated backup for your network switches with WinSCP and PowerShell you can take things one step further and with a little more PowerShell its possible to get email reports on any changes between switch configs.

This kind of setup would be useful for any sized organisation who have a need to ensure changes are logged or want to ensure that no one has maliciously changed a configuration.

Make sure you edit lines 6-8 with your SMTP details

Make sure you edit lines 6-8 with your SMTP details

The setup is simple, just as with the automated backup these will need to be extracted to your C:\Network Switch Backup folder which should look something like the screenshot to the right once done.

I’ve also included an updated .cmd file which calls the Backup Network Switches.ps1 script and then the Compare Configs.ps1 script in turn.

  Network Switch Change Log (1.6 KiB, 198 hits)

There is plenty of description within the PowerShell file; even a little error handling as well! Be sure to edit lines 6-8 with your SMTP settings.

Procurve 5406R zl2Although it may not be the most glamorous side of IT every sysadmin will appreciate the value of a rock solid backup system. All too often though these systems do not extend down to the ’embedded’ systems like network switches and firewalls.

However with a little WinSCP (and its fantastic .NET assembly automation package) and PowerShell combined its pretty easy to cook up something that is 100% less of the cost of any management solution.

This guide shows how to setup the backup of a HP ProCurve switch (I’ve tested it with the ProCurve 8200 series, 5400 series the 2920s, a 2626 and a 2530 all of which were running the most recent firmware) although it should be a simple matter of changing the relevant paths to make it work with other manufacturers kit (e.g. Cisco).

1Download Source Files

First up grab the source files from the link below and extract the contents to C:\Network Switch Backup (you can use any other path but will just need to update the paths inside the PowerShell) you should then have a folder which contains a .cmd file, a .ps1, a sample .csv and a sub folder called Backups.

  Network Switch Backup (1.7 KiB, 304 hits)

Getting your Switch ready and filling out the CSV

Each switch will now need ip ssh and ip ssh filetransfer running on it through the CLI (if its not already setup); be sure to set a manager password (if you haven’t done so already!) as well. In addition you will need to find the Server host key fingerprint for each switch; the screen shots below show one way of doing this.

Continue reading

Have been having a bit of an interesting issue over the past few weeks whereby our Hyper-V Hosts (Dell T430 Tower Servers) would loose network connectivity at seemingly random intervals; the only resolution was to restart the server or to remove and replace the network cable.

After much investigation looking at the servers and associated network switch we discovered that only the Virtual Switches attached to the on board Broadcom NetXtreme adapters were having issues and that the Intel PCI card NICs were not.

That soon lead onto Microsoft KB 2986895 which relieved a known bug in the drivers for the Broadcom adapters that messed up the Virtual Machine Queues (VMQ) feature of Hyper-V causing a loss in network connectivity. The fix is either to update the driver to a version that does not have the issue or to disable VMQ.

More details can be found in this Microsoft KB… https://support.microsoft.com/en-us/kb/2986895

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