Monthly Archives: September 2015

Cisco VWIC3-1MFT-T1/E1 Controller PRI Issue

Hats off to Dan, my co-worker….he’s been chasing a PRI issue at one of our new sites. He has a Cisco 2951 router with a VWIC3-1MFT-T1/E1 card installed, and when the PRI circuit is un-plugged and plugged back in, the circuit refuses to come up. However, if you reboot the router, the circuit will come up. (Rebooting the router is not a good fix, just in case you are wondering.)

As part of his troubleshooting, he replaced the VWIC3 card with a VWIC2 card and it works just fine…no issues. After working with Cisco TAC, he found out he was hitting a known bug with this VWIC3 card and IOS software (15.3(3)M6). At least the fix was easy…he simply had to add the command “hwic_t1e1 equalize” under the controller T1 interface…like this…

Adding in the hidden controller T1 command

Adding in the hidden controller T1 command

What’s interesting is it’s a hidden command…if you list the available commands under controller T1 0/0/0, you won’t see this command…

A hidden command...interesting!

A hidden command…interesting!

And I just bet there are a bunch more hidden commands that we don’t know about!!

A Good Laugh for a Friday!!

So, did you hear that China and the US have agreed to no longer engage in cybertheft against each other? No…I’m serious. Really. Take a look at this…

CNN Report – US & China Agreement

See…I told you!

When I first heard this I just laughed. Is today April 1st??  Way too funny. I’m just sure that China will now curtail their state sponsored cyber warfare. No…seriously…I’m sure they will.

Oh…and I saw some pigs flying today too!!

Installing DIG on a Windows Machine

First up…a quick apology. Back on April 10th, I posted Verifying Proper Email Routing – MX Records. At the end of the post I mentioned I would talk about the trailing dot shown in the DNS records in my next post. Well, I basically forgot. Life just got too busy.

But before I do that, you really need to get DIG installed on your Windows PC (if you have Linux then you should already have DIG). So today, lets get DIG installed and tested…this is a great tool to have, and you will be surprised at how often you will use it.

The package we are going to install is BIND (Berkeley Internet Name Domain) from ISC (Internet Systems Consortium). ISC has been around for years, and most DNS servers on the Internet run BIND (whether Windows or Linux/UNIX based). Do the following…

  • Go to https://www.isc.org/downloads/bind
  • There is a lot of good info on this page concerning BIND and DNS…I would recommend reading this when you have a chance.
  • Click on Download BIND button
  • Expand the BIND menu
  • Click on the Download button to the right of the GREEN “Current-Stable” status
  • In the window that pops open, choose the correct version for your system…(click the appropriate blue box)
  • Next, create a directory in your C: drive called “bind”, move the BIND ZIP file to that directory, then double-click on the ZIP file. Extract all of the files in the \bind directory.

Now, lets test. Open up a command prompt and change to the BIND directory, then type in “dig” and press enter.  You should see something like this…(this example is showing DIG returning a list of the ROOT servers on the Internet)…

Running DIG at the command prompt

Running DIG at the command prompt

If it doesn’t work, there are a couple of common errors which are easily fixed…

32 bit installation error:  You may get an error stating “The application has failed to start because its side-by-side configuration is incorrect”.  If that’s the case, run the file “vcredist_x86.exe” which is located in the same “bind” directory. Then try running “dig” again…it should work.

64 bit installation error:  If you get the error message stating that MSVCR110.DLL is missing, then do a search on the C: drive for that file, and copy it to the “bind” directory. Running “dig” should now work.

Now you can play with DIG…some examples…

Some DIG examples

Some DIG examples

DIG is very powerful, and will quickly become your go-to tool when you have any DNS issues. I will talk more about using DIG in a future post.