Mod security will increase the security of your server, but sometimes it's blocking legitimate traffic. If you want to disable it for a single domain on your Plesk server, this is what you need to do:

1. Create a vhost.conf file and place it in the following directory:
   
   /var/www/vhosts/domainname/conf
   
   
2. It should include the following:
   
   <IfModule mod_security2.c>
   SecRuleEngine Off
   </IfModule>
   
   
3. Reconfigure Apache:
   
   /usr/local/psa/admin/bin/websrvmng -u --vhost-name=domainname.com
   
   
4. Restart Apache:
   
   service httpd restart

That's it, Mod Security is now disabled for this single domainname...

In case you are not sure what a buffer overflow exactly is, check out the following animation. It explains very well what it is...

Buffer Overflow Animation

A couple of weeks ago I launched GNS3Vault, you can download any Cisco Lab you like here for free and use it with the GNS3 software.

This is ideal when you are studying for your CCNA, CCNP, CCSP, CCIP or any other Cisco certificate. Even if you just want to upgrade your network knowledge this is a good place to check out.

If you haven't seen the website yet, here's the link:

http://www.gns3vault.com

Have fun, and good luck studying!

Rene

Hello all,

In case you are studying for you CCIE and are not sure what the DOC CD is about, and how importance it is...please check out this great link explaining it all:

DOC CD - IP Expert

I found a nice little overview of some IOS features that are possible on a Cisco router, some of them are enabled by default and possibly a security risk..it's a good idea to check them out and perhaps disable them on your network!

1. CDP: We all know CDP, the Cisco Discovery Protocol. It's a layer2 protocol that will tell your all the information about your neighboring devices..IP address, hardware, IOS version and so on. If you don't use it, disable it.
2. TCP Small servers: This is some TCP standard network services like echo, disable it.
3. UDP Small servers: Same but for UDP, disable it.
4. Finger: User lookup service, originally for Unix. Can be used remotely to list logged in users. Nobody needs to know this kind of information remotely...
5. HTTP server: very nice for in a lab (www.gns3vault.com) but not a good idea in a production environment.
6. Bootp server: Allows other routers to boot from this router, hardly ever used...
7. Configuration auto-loading: Your router will try to boot up from a TFTP, i've only used this once so my regular 2600's could boot the XM image in a lab...not gonna use it in production.
8. PAD service: Router will support X.25, not gonna use it.
9. IP Source routing: allows the creator of an IP packet to choose the route, you don't want this.
10. Proxy ARP: Your router will answer (proxy) for L2 ARP requests, don't use this.
11. IP directed broadcasts: Allows you to send packets to the broadcast address of another subnet, allows "smurf attacks". Used for DOS attacks...so disable this.
12. IP Unreachable notifications: Your router will notify a sender of incorrect IP addresses, gives away information.
13. IP Mask reply: Router will send the subnet mask of an interface in response to a ICMP mask request, gives away information.
14. IP Redirects: Your router will send an ICMP redirect in response to some router IP packets.
15. Maintenance Operations Protocol (MOP): Old management protocol, part of DECNET.
16. NTP service: Your router can become a time server, perhaps not needed.
17. SNMP: If you don't use SNMP, I'd suggest to disable/block it.
18. DNS: Routers can perform DNS lookups, if you don't use this i'd disable it.

Is there anything else that you miss in this list? please let me know!

Good luck securing your routers!

When you are using rsync to copy/synchronize files from A to B it's very useful to know that it's possible to set a Bandwidth Limit. This is very nice for remote backups so your internet connection won't be 'choked'

Take a look at this video explaining it:

Or if you just want the command:

rsync --stats --progress --bwlimit=750 -auv /FolderA /FolderB

When you are studying for any networking-exam like Microsoft's, Cisco or from any other vendor it's useful that you know how to perform binary and subnetting calculations.

Also for work it might be very useful to know how to create the correct summarizations and to see in the blink of an eye what the broadcast address, network address and the number of hosts of a given ip+subnetmask is.

To make your life easier I decided to create an eBook which explains you exactly how to do it and i'll teach you my strategy how to solve these questions fast...off the top of your head!

I'm inviting you to take a look at this page.

Are you studying for your CCIE R&S but do you have no idea what the real exam will look like?

Cisco created a very nice video showing you what the Lab exam will look like! Strongly recommended to watch this before you go take the exam:

CCIE R&S Lab Exam Demo

Whenever i'm in the train, car or at the gym I like to listen to some podcasts, for me it feels like i'm spending my time better then listening to for example the radio, or watching TV while doing some cardio exercises.

One of the podcasts I like are from the "Packet Pushers". A couple of CCIE'ers decided to have some discussions and record them for you to download, it's very cool to listen to!

Check it out at:

http://packetpushers.net/

Ever wanted to know more about Linux, but never found the right book?

There are no excuses anymore, there's a great free book you can download called "GNU/Linux Advanced Administration".

Chapters:

1. Introduction to the GNU/Linux operating system
2. Migration and coexistence with non-Linux systems
3. Basic tools for the administrator
4. The kernel
5. Local administration
6. Network administration
7. Server administration
8. Data administration
9. Security administration
10. Configuration, tuning and optimisation
11. Clustering

So what are you waiting for? Go grab this book over here:

FTA Academy