Network NUTS Videos Viewership May 25, 2012
Posted by networknuts in linux training in india, Red Hat, rhce, rhce training, RHCSS.Tags: free linux tutorials, linux training, linux videos, networknuts, rhce training india, rhce videos, rhcss training india
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Network NUTS YouTube channel viewership.
Wondering about 0% of Pakistan and Australia.
Network NUTS YouTube Videos Viewership
Use PAM to force users for new password May 23, 2012
Posted by networknuts in linux training in india, Red Hat, rhce, rhce training, RHCSS.Tags: alok srivastava, best linux training, force new password linux, force password use, linux hacks, linux tips, linux training, networknuts, redhat delhi, redhat india, redhat training, rhce exam, rhce training delhi, rhcss exam, rhcss training delhi, securing linux, using new password, using pam
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If you want to force users not to use the earlier used password again. You can take the help of PAM.
Just edit the file “/etc/pam.d/system-auth” and append the word “remember=10” in the password sufficient line. In this case I am telling the PAM to remember last 10 used passwords. So the users will be forced to use new passwords.
Here is the screenshot of the job executed on my machine.
Using PAM to force new passwords
I deserve “like”, “comments” and “share” for all the photo-editing job that I had done. 
You can also view this post on Network NUTS Facebook Page.
Preventing against SYN attack May 22, 2012
Posted by networknuts in linux training in india, Red Hat, rhce, rhce training, RHCSS.Tags: alok srivastava, iptables, iptables configuration, linux hacks, linux tricks, networknuts, preventing syn attack, securing linux server, syn attack, sysctl.conf
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How to Discourage SYN Attack.
A SYN flood attack is a type of DoS attack.
A SYN packet notifies a server of a new connection. The server then reserve some memory to handle the incoming connection, sends back an acknowledgement, then waits for the client to complete the connection and start sending data. By spoofing large numbers of SYN requests, an attacker can fill up memory on the server, which will sit their waiting for more data that never will arrive. Once memory hasfilled up, the server will be unable to accept connections from legitimate clients. This effectively disables the server.
There are two simple methods you can use to discourage SYN attack.
#1. Configure /etc/sysctl.conf file and make sure “net.ipv4.tcp_syncookies=1″.
#2. Configure IPTables to reject packets if they are not SYN.
iptables -A INPUT -p tcp ! –syn -m state –state NEW -j DROP
Below is the screenshot from my machine.
Preventing against SYN attack
Network NUTS Videos Feedback May 21, 2012
Posted by networknuts in linux training in india, Red Hat, rhce, rhce training, RHCSS.Tags: alok srivastava, free hacks, linux training feedback, linux tutorials, linux videos, linux videos feedback, networknuts
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What a Comment Sir ji … with beer ….. posted on Network NUTS YouTube Channel.
What else is needed in summers.
Keep it up guys .. ur beer (oops comments) motivates us like anything.
Linux Videos Feedback
1000 subscribers on YouTube channel May 21, 2012
Posted by networknuts in Indian Networking Institute, linux training in india, Red Hat, rhce, rhce training, RHCSS.Tags: alok srivastava, free linux videos, linux hacks, linux tutorials, linux videos, networknuts
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Huuuuaaaahhhhhhhhhhhhhhhhhhhhhh
Just hit the 1000 subscribers mark on Network NUTS YouTube channel.
http://www.youtube.com/user/networknutsdotnet
Making us the only channel in India by a IT training company
Network NUTS YouTube Channel Subscribers
with that number of fans and subscribers.
Love you all.
Video on “Log & Lock using IPTables” May 21, 2012
Posted by networknuts in Indian Certified Networking Institute, Indian Networking Institute, linux training in india, Red Hat, rhce, rhce training, RHCSS.Tags: alok srivastava, free linux videos, free redhat videos, iptables configuration, linux hacks, linux videos, log iptables, networknuts, redhat delhi, redhat india, redhat linux training, redhat training, redhat videos, rhce exam, rhce training, rhce training delhi, rhcss training, rhcss training india
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IPtables to control range of ports and IP May 20, 2012
Posted by networknuts in linux training in india, Red Hat, rhce, rhce training, RHCSS.Tags: alok srivastava, block ip address, block network port, iptables configuration, linux training delhi, networknuts, rhce training, rhcss training, securing linux
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I know.. I know that Sunday is for total rest. But if you get time on Monday, then it can be useful.
Lets configure IPTables to block a range of ports as well as range of IP’s.
Here I am blocking port 20 and 21 for IP range 192.168.0.250 to 192.168.0.253.
iptables -A INPUT -p tcp –destination-port 20:21 -m iprange –src-range 192.168.0.250-192.168.0.253 -j REJECT
This will do the job.. but you are not forced to do it today i.e. on Sunday.
“Like” it, “share” it, “use” it
Here is the screenshot from my machine for this tip.
Do “like” the Network NUTS Facebook Page.
Using IPTables to control range of ports and IP’s
Network NUTS Awards May 18, 2012
Posted by networknuts in Indian Networking Institute, linux training in india, Red Hat, rhce, rhce training, RHCSS.Tags: best red hat training partner, linux delhi training, linux training, networknuts, redhat delhi, redhat india, redhat linux training
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Just sharing the good times.
Network NUTS winner of “Best Red Hat Certified Training Partner, North India“.
Without you, nothing is possible.
Thanks all for your love and trust.
Best Red Hat Training Partner, Network NUTS
Block or Allow port ranges using IPTables May 17, 2012
Posted by networknuts in linux training in india, Red Hat, rhce, rhce training, RHCSS.Tags: alok srivastava, best linux training institute in india, block ftp, iptables, linux delhi, networknuts, port range, redhat delhi, redhat india, rhce delhi, rhce exam linux tip, rhce training, rhcss delhi
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You can use the IPTables to block a port range with a single statement, rather than writing the same line again and again.
Below is a simple example where I had blocked FTP ports 20 and 21 using a single line. Thus reducing my keystrokes.
iptables -A INPUT -m state –state NEW -m tcp -p tcp –dport 20:21 -j REJECT
Here is a step by step screenshot from my machine, for the tip.
Don’t forget to “like” and “share”. Also view this post on Network NUTS Facebook Page.
Using IPTables to allow or block port range
Network NUTS reaching Brazil & Jordan May 15, 2012
Posted by networknuts in linux training in india, Red Hat, rhce, rhce training, RHCSS.Tags: alok srivastava, networknuts
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Network NUTS Facebook page reaching out to Brazil and Jordan.
Fans from USA need to work hard. They have just lost their second position, to Brazil.
Network NUTS Facebook Page reach
