blindhog.net

This short post demonstrates using ‘ip sla’ and  freedns.afraid.org for dynamic dns.

(more…)

The company I work for has been implementing thin client technologies based on Citrix and Microsoft Terminal Services for a long time.  Today, VMWare’s Virtual Desktop Infrastructure (VDI) is starting to be the hot item.  This post addresses the network concerns presented by thin client technologies.  My first experience with this issue was presented by a small branch employee playing ‘Wheel of Fortune’ online.  The network died every time it was her turn to spin the wheel.

(more…)

I recently had the pleasure of installing my first 3G enabled routers in a production environment. To my pleasant surprise, the process and configuration is very simple. I was able to follow Cisco’s documentation to the letter. From zero to DMVPN took about 3 hours.

Although the configuration is simple, I still got confused about a couple of parts on my first try … basically just over thinking.  Also, there were a few issues maintaining  solid connectivity but I will just chalk that up to inexperience.

(more…)

If you work on Cisco IPT environments, you have probably ran into a situation where you wanted to make a call through a gateway to test the PSTN connectivity, test translation-profiles or as a process of elimination, you wanted to eliminate the CUCM cluster.  The Xlite SIP softphone is a great tool for such tests. You can make calls through an IOS gateway without making any new configuration changes to the gateway itself or to the CUCM cluster.

(more…)

Before getting started with this little tip, I just wanted to drop a short note to you all to let you know that James and I have not abandoned the blog. We have just taken an “unannounced” three month vacation. Or you could say that “life happened” to us both and three months slipped by.

I have been trying to find the time to put together something really impressive after being out for so long, but I have decided it is better to just get back to work. As a way of getting back into the swing of things, I thought I would do a small writeup on an IOS feature that I recently stumbled across. I have known for a while that it is possible to pass commands between Linux machines via ssh by simply adding a command to the end of the ssh command string. I recently tried it on a router and to my surprise … it worked. Cool!

(more…)

In this tutorial, you will learn a couple ways to connect a physical router to your home phone line as part of your “virtual voice lab “.  An all virtual voice lab would be ideal. However, real hardware is necessary for a more complete voice lab. I will be using a 2611XM for my home lab, but you can use just about any Cisco router with a couple fxs and fxo ports.

(more…)

Here at Blindhog.net, we have issued tutorials for connecting Windows or Linux to a physical network using gns3, but apparently, there is a little difference for MacOSX.  I recently received an email from one of our readers, Ivan Pletenev. Ivan describes how to connect GNS3 to internet through wifi-interface in MacOSX. You will find his writeup below. Thanks Ivan!

(more…)

I apologize for the delay in posting the next tutorial in the virtual voice lab but I ran into a problem communicating from the HQ router to the host Ubuntu server. I thought I was able to communicate from the HQ router to the host during the Headquarters build tutorial….but I was wrong.

(more…)

This is the Frame-Relay WAN section of the Virtual Voice Lab. In this tutorial, you will learn how to connect Branch 1 and Branch 2 routers to the Headquarters router using frame-relay PVCs.
(more…)

Is it possible to build a voice lab without actual hardware? The answer is yes and no. You can build a very good lab using GNS3 and VMWare but it is not possible to build a complete lab. The underlying emulation engine for GNS3 (dynamips) does not support digital signal processors (dsps) or voice cards.

Over the next few months, I will show you how to build a very good lab without any hardware. If you want a more complete lab, you will need to obtain at least one router with dsps and voice cards. I have a 2611XM router with DSPs, a vic-2fxs card, a vic-2fxo card and an ATA-186.

(more…)