Tachytelic.net

Technical Posts

VMWare Workstation Host unable to ping or access guests over the network

by 1 Comment

This is going to be a quick post as I just wanted to get the information out there for anyone else having the same problem as me. I had a situation where VMWare Workstation was working fine, but I was unable to access any of the guests from the host, the situation was like this:

  • Guests could reach the internet and the rest of the LAN.
  • Other machines on the LAN could reach the guests.
  • VMWare Workstation Parent was unable to ping or access the guests.
  • The guests were unable to access the parent over the network.

I spent a long time messing around with the virtual network configuration, uninstalling VMWare Workstation, even paid to upgrade from version 12 to version 14. But nothing worked.

In the end I started looking at the network configuration of the host, which didn’t seem to have anything out of the ordinary. I did have SonicWALL Global VPN client installed, which I did not suspect would cause any issues, but out of desperation I uninstalled it and then everything worked great.

So if you have any 3rd Party VPN clients installed, try uninstalling them and see if that fixes your issues. I did try disabling the SonicWALL adapater at first, but that did not make any difference.

Unable to Print to Epson Dot Matrix printers after Windows Updates

by 126 Comments

I received a call from a customer today who was suddenly unable to print to Epson Dot Matrix printers, after a LOT of troubleshooting I figured out that this is due to a Windows update.

Printers I can confirm that are not working after the updates are:

  • Epson LQ-300
  • Epson LQ-300+ II
  • Epson LQ310
  • Epson LX300
  • Epson LQ2180
  • Epson LQ2190
  • Epson LQ730K

Windows Updates have been issued for Windows 7, 8 and 10 and they are all having the same issue. The updates are:

There may be other updates which I am not aware of yet.

To get your printers working again, the quickest way is to remove the offending update. As you might not be sure which update you have installed. The quickest way is to run the following commands in an elevated command prompt:

wusa /uninstall /kb:4048952 /quiet /warnrestart
wusa /uninstall /kb:4048953 /quiet /warnrestart
wusa /uninstall /kb:4048954 /quiet /warnrestart
wusa /uninstall /kb:4048955 /quiet /warnrestart
wusa /uninstall /kb:4048957 /quiet /warnrestart
wusa /uninstall /kb:4048958 /quiet /warnrestart

Until Microsoft release an updated security patch you can temporarily block the patch using this tool from Microsoft:

Microsoft Patch Blocker

Or if you are using WSUS then you can block the patch from there. This is really a difficult problem to resolve if you don’t realise that the problem is being caused by an update, because you wouldn’t expect an old Dot Matrix printer that has been working fine for years to be impacted by a Microsoft Security Roll-up.

I don’t know if this is happening to other Dot Matrix Printers besides Epson at the moment.

Microsoft have updated the KB articles to acknowledge that these updates are the cause of the problem:

Update 21/11/2017 – Problem has been fixed by Microsoft

Microsoft have now issued an updated patch which will should download automatically via Windows Update, but if you want to grab it manually it can be found here:

https://support.microsoft.com/en-us/help/4055038/november-21-2017-kb4055038

Setting the primary email address for Office 365 users with PowerShell

by 1 Comment

It’s easy to Set the Primary Email Address on Office 365 with PowerShell using the Set-Mailbox cmdlet. The primary address is defined using “SMTP” in uppercase in the email address. For example:

Set-Mailbox -Identity "test.user" -EmailAddresses SMTP:test@tachytelic.net,smtp:test2@tachytelic.net

Note: The Set-Mailbox cmdlet will remove all existing aliases, so include them with the command.

Enter the details of the mailbox to be changed in the form below, and PowerShell code will be generated. It includes the required PowerShell to connect to Office 365.

Set the Primary Email Address on Office 365 using Powershell

 

Example of the Powershell Code changing the Primary SMTP Address

Set the Primary Email Address on Office 365 when the user is being managed by the local active directory

The steps above will work if the user that you are changing is cloud managed. If your accounts are synchronised from your local active directory, then they will be out of the write scope of Office 365. If that is the case please follow the instructions on this page:

https://tachytelic.net/2018/08/office-365-how-to-change-primary-email-address/

Install an Intel P3520 SSD into a 11th Gen PowerEdge

by Leave a Comment

We are still running some 11th Generation Dell PowerEdge servers in our DC and some of the virtual machines were having some performance issues. We considered completely replacing replacing the servers, but found that the CPU load was very low most of the time.

The bottleneck for the database application running on these servers was disk related and we felt that a boost in performance in this area would bring the performance back to where we needed it to be. We decided to put an Intel P3520 NVMe SSD into two of the machines. This card, although not top of the range in terms of performance, has a great price/performance ratio and should be much faster than the existing drive array.

The specification of the server we put them into:

Dell PowerEdge R510
2 x Intel XEON X5670
128Gb Ram
PERC H700 1Gb (For Hard Drives)
VMWare ESXi 6.0.0.5050593

Here is the card in the server PCI slot:

VMWare recognised the card no problems, but I also installed the Intel NVMe drivers, which boosted the performance a bit. I haven’t done extensive performance testing but I can tell from using the applications hosted on the machine that it is much quicker.

Disk Benchmark with the Intel P3520 NVMe ssd:

And for comparison the 8 disk SATA array on the PERC H700:

So overall adding the Intel SSD provided a significant boost in performance over the existing array, which is now just there for redundancy, the application performance has boosted much more than the performance metrics above signify.

Correct putty settings for use with SCO Openserver 5.0.7

by 4 Comments

After so long since it was it was in mainstream use I am still doing regular work for customers with SCO Openserver, gradually they are all coming off the platform, but while it is still in use it’s nice to have the best possible experience.

A lot of the time if I am in a rush I will just use the Windows telnet client to connect to SCO Servers but really putty is so much nicer and you only need to change a few settings to get great compatibility with SCO.

Specific settings for using Putty as a Telnet client with SCO

Keyboard settings

Change your keyboard settings to:

Backspace Key sends Control-H
The Function keys and keypad set to SCO

Window Settings

Change the remote character set to ISO-8859-2: 1999 (Latin-4, North Europe).

Terminal Type

Set your TERM environment variable to xterm and you should have a decent looking display and emulation when using SCO.

Personally I sometimes like to have a 132 column width display which you can easily do by setting the terminal type to ansi-w in SCO and then changing the number of columns in putty to match.

Exit mobile version