Country IP Blocking

Country IP Blocks provides an online, search able internet protocol (IP) address database with the ability to export specific country level IP blocks into CIDR, Netmask, IP Range, .htaccess deny, .htaccess allow, Decimal/CIDR and Hex/CIDR formatted files. These files can then be used in cojunction with server (e.g. Apache, Microsoft IIS) and network security devices (e.g. Cisco, Juniper, TippingPoint, Untangle) to create access control lists to block access to networks and systems from specific countries.

Whilst I don’t advocate blocking entire countries, there are known IP address blocks used by spammers, crackers and other Internet filth which may need to be blocked from some websites and systems.

The American Registry for Internet Numbers (ARIN) and the Asia Pacific Network Information Centre (APNIC) manage the majority of Internet routed IP addresses allocations for IP v4 and maintain online allocation databases which are made available to Internet service providers. The Country IP database is updated with this information at least once every 24 hours which means accurate global network data is provided.

In terms of Country IP Blocks site, I specifically like the ability to export IP lists into common access control list formats such as HTACCESS. A simple example Continue reading “Country IP Blocking”

MTR – The Network Diagnostic Swiss Army Knief

MTR, a Linux shell command, combines the functionality of the ‘traceroute’ and ‘ping’ programs in a single network diagnostic tool.

When MTR starts, it investigates the network connection between the host MTR runs on and HOSTNAME (e.g. www.google.com), by sending packets with purposly low TTLs. It continues to send packets with low TTL’s, noting the response time of the transit routers. This allows MTR to print the response percentage and response times of the internet route to the remote host. A sudden increase in packetloss or response time is often an indication of a problematic or saturated link.

Compared to mixing and matching ping and traceroute commands, MTR is a true network diagnostic swiss army knief. For those bound to Windows destkops, Microsofts command link “pathping” is similar to MTR but lacks the real time tracing and statistical data.

MTR Example:

[shell] Continue reading “MTR – The Network Diagnostic Swiss Army Knief”

z Shell!

For those new to the Linux world and taking their first steps into SHELLS, two helpful downloads are available:

1. The One Page Linux Manual is available here.

2. Linux Command Reference is available here.

Both of these documents are dated but provide a solid outline of common shell commands including such functions as creating directores, ziping files, configuring network interfaces, mounting devices and search functions. These are a must for any Linux enthusiast!

Do you know of any other online one pager Linux command PDF’s?

New Site!

I’ve been planning to re-do and re-launch the md3v.com site (and all its aliases) for some time but haven’t had the time. After reviewing options, I came to the conclusion that sometimes simple is simpler and have decided to settle on WordPress as content management system.

My plan for the site is to post technical documentations, project information, blurbs about technology and other random items. I hope to consolidate a large number of technical how-to’s into a single location. After the previous md3v.com incarnation fell apart, its my hope that this site will be a long term resource.

I will post articles as often as I’m able to and look forward to input and idea’s. Bare with me as I get various site components up and running.

Cheers…