Howto: Upgrade Linux Kernel

How do I upgrade my Linux kernel? I would like to upgrade kernel without compiling from source code i.e. binary upgrade. How do I perform the actual upgrade of the kernel in Linux?

You need to compile kernel only if:
=> You need custom made kernel for specific task such as embedded kernel.
=> Apply third party security patches.
=> You need to apply specific patch to Linux
Upgrade of the kernel in Red Hat enterprise Linux version <= 4.x
If your system is registered with Red Hat Network (RHN), then you can use the up2date command as follows:
# up2date -f kernel
For SMP kernel (multi core or multiple CPU) use command:
# up2date -f kernel-smp
Upgrade of the kernel in Fedora Linux / CentOS / RHEL 5
Use yum command to upgrade kernel:
# yum update kernel
If you have downloaded RPM file use rpm command:
# rpm -ivh kernel*

portnumbers in servers

port number application
21 ftp
22 ssh
23 telnet
25 smtp mail port
53 dns port
67 dhcp server
79 finger command for smtp mail server ETRN finger port
80 http port
110 pop3 port
115 sftp port
123 network time protocal port
143 imap4 port
177 xmanager port tcp
389 ldap port
443 hhtp port (ssl)
445 microsoft active directory and smb protocal port
465 google mail outgoing mail server
636 ldap(ssl)
993 secure internet message access protocalport
1433 sql server port
1434 sql server monitoring port
1521 oracle port
2000 cisco ip phone port
3306 default mysql port
3389 remote desktop port and terminal server port
5900 real vnc default remote control port
6000 tcp port for xmanager port
8080 http internet traffic port

Root user login on VSFTP

As you know ftp servers normally wont allow to login as root user or any of the local user (Example : daemon,bin, sys, nobody…etc) due to security and preventing the ftp servers from ftp brute force scanner attacks. If you still want to enable root user login on vsFTP for some reasons, here is a short tutorial which allows you to do that.

Enabling Root User Login On VSFTP

SSH your server as root and then search for the files ftpusers, vsftpd.users (or) user_list (on Centos the locations should be under the /etc/vsftpd or under /etc). Edit the files on your favorit editor and remove the ” root ” from the list of users. Now edit the /etc/vsftpd.conf file and enable/uncomment the following two lines :

# vi /etc/vsftpd.conf

local_enable=YES
userlist_file=/etc/vsftpd/vsftpd.users (if exist)

Restart the vsftpd server to load with the new configuration.

# /etc/init.d/vsftpd restart
Now try login as root via ftp and see how it goes.

Find Out CPU Architecture Information on Linux

You can use /proc/cpuinfo file or use the lscpu command to get info about CPU architecture.

$ less /proc/cpuinfo

Or

$ lscpu

Disabling USB ports

If you administrating a small or large workstations running with Linux Desktops and want to disable the USB ports for security so that no one can copy the data via pen drive, try the following steps to disable the USB port(s).

Edit the grub.conf and add the following lines(you need to login as root).
# vi /boot/grub/grub.conf

Then add the following lines on the right kernel version

kernel /vmlinuz<your-kernel-version> rhgb quiet nousb

Save and exit the file and reboot the system to disable the USB ports and the boot time.

How To Call Your Friends With Their Own Number....

How To Call Your Friends With Their Own Number....

 Mobile hack to call your friends:

1. Go to  http://www.mobivox.com and register there for free account.


2. During registration, remember to insert Victim mobile number in "Phone number" field as shown below.


3. Complete registration and confirm your email id and then login to your account. Click on "Direct WebCall".


4. You will arrive at page shown below. In "Enter a number" box, select your country and also any mobile number(you can enter yours). Now, simply hit on "Call Now" button to call your friend with his own number.


5. That's it. Your friend will be shocked to see his own number calling him.