Author Archives: Mihai

About Mihai

I'm a network administrator and technology lover. I keep this blog in my spare time as a notebook (a small wiki if you want) of my experience in the IT field.

Romanian VoIP providers – Geotel – (III)

Geotel is another VoIP provider that gives you the possibility to take your own landline number with you where ever you go in the world. The company is based in Suceava (a city in the northern part of Romania).

Sound quality Ok
The prices Are a little high. They can charge you between 0.015 E – 0.025 E per minute on the land-line network. The list of all connection prices can be found here: http://www.geotel.eu/tarifeprepay.php
Are the phone calls in the provider’s network free? Yes!
Does it have a Voice mail? Yes! *
It is advertised but I did not see the option on the configuration platform
Does it have a cost control service? Yes!
Does it have a STUN service? Yes!
Can you buy the credit On-Line? Yes! (through various ways like:  PayPal and ePayment)

 

The good stuff:
One of the obvious parts when you first see their webpage is that you will get 25 minutes for free once you are registered for a limited period and unlimited phone calls in the Geotel network (see here http://www.geotel.eu/support/index.php?pid=knowledgebase&cmd=viewentclient&id=11). Continue reading

A new monitoring tool is in town…

Watching the “Network Monitoring Application of the Year” vote on http://www.linuxquestions.org I have noticed a new Nagios / competitor: Shinken. The name describes a very sharp Japanese sword – associating the program with its large scale monitoring capabilities.

The software it’s written in Python and it’s compatible with the Nagios configuration. Also they say that they use fewer resources than the Nagios counterpart. The developer has put an accent on the Business rules, Cloud computing and “Very large monitoring capabilities”. Take a look at their features: http://www.shinken-monitoring.org/features/ Continue reading

Backing up a highly utilized MySQL db

After I have done a research on the web I have found that the best method is by using LVM. We will need to lock (temporarily) the tables, flush the changes to the disc, do a LVM snapshot of the directory that contains the MySQL data and unlock the tables again.

Continue reading

Small routing script

In recent days I was confronted with a problem regarding the routing under Linux.

The request was to add a route on a Proxy ARP server.

The Linux OS does give you the possibility to do add a route, in an “automatic mode”, in ways like:

  • add a route on the interface configuration (it will be applied only when the interface will go on-line) – for example Ubuntu and SUSE Linux
  • add a route on the network start script
  • add a route in the static-routes file
  • add a route with a script on the ifup folder on the “/sbin/ifup” (here more details: http://www.comptechdoc.org/os/linux/howlinuxworks/linux_hlsysconfig.html)

But because this was a complicated setup I was forced to use a bash script under the “/sbin/ifup”.

The script looked like this:

#!/bin/sh
ROUTE_CMD=”/sbin/route”
DMZ_INTERFACE=”eth0″               #we should have an IP address on this network – 85.14.228.0/24
LAN_INTERFACE_1=”eth1″          #we should have an IP address on this network – 10.12.0.0/24
EXTIPADDR=”85.14.228.254″     #an dmz gateway
INTIPADDR=”10.12.0.254″           #all the internal traffic

$ROUTE_CMD add -host 85.14.228.248 gw $EXTIPADDR $DMZ_INTERFACE
$ROUTE_CMD add default gw $INTIPADDR $LAN_INTERFACE_1
exit 0

I hope that this is going to help you,

Mihai out!

Monitoring Keepalived with Nagios

This is one of the cases where the passive check of the Nagios monitoring system comes in handy as we need to be informed immediately when the Keepalived changes state. So you will need an NSCA system implemented with your Nagios configuration.

Studying the Keepalived configuration we found that the authors have implemented the option to run a script that when the state of the VRRP changes. The script I’m referring to is run under the “notify” option.

Continue reading

Configuring the radius authentication with Cisco Wireless Control System 6.0.196.0

When I tried to make a radius based authentication system with our Cisco Wireless Control System (WCS) I was hit by the lack of documentation of this feature. The only valid links I have found is this one:

https://supportforums.cisco.com/thread/339057?tstart=0

It is pretty old (Dec 12, 2007) & it did not fitted entirely with my new WCS installation. And as a result I made this one so anybody else could cover the holes. Continue reading

I know what “I” did last summer!

Having a little time off from the day to day responsibilities I usually have at my work place, last summer I decided to build the map of Italy with all the offices, for our Help Desk.

So, with the magic of Wikipedia (http://en.wikipedia.org/wiki/Italy), Gimp and Mk-livestatus I have done in NagVis, a dashboard that displays live checks of the network and server software. This map is displayed on a TV in the Help Desk room, so that everyone can see the network status. Continue reading