Linux Blog

Enable Root logins to Telnet and FTP Services

Configure Telnet for root logins

Simply edit the file /etc/securetty and add the following to the end of the file:

pts/0
pts/1
pts/2
pts/3
pts/4
pts/5
pts/6
pts/7
pts/8
pts/9

This will allow up to 10 telnet sessions to the server as root.

Configure FTP for root logins

Edit the files /etc/vsftpd.ftpusers and /etc/vsftpd.user_list and remove the ‘root‘ line from each file.

Make sure that you NEVER configure your production servers for this type of login.

Uninstalling the Linux Boot Loader - OpenSuse

YaST can be used to uninstall the Linux boot loader and restore the MBR to the state it had prior to the installation of Linux. During the installation, YaST automatically creates a backup copy of the original MBR and restores it on request.

To uninstall GRUB, start the YaST boot loader module (System+Boot Loader Configuration). In the first dialog, select Reset+Restore MBR of Hard Disk and exit the dialog with Finish.

Reboot the system and you will get your old bootloader.

HowTo work with cpio files

To extract a cpio file:
cpio -iv <>

To list the contents of a cpio file:
cpio -itv <>

To create a .cpio file with all files in the current directory:
ls | cpio -o > cpio_file

Run Adobe Photoshop and Dragon Naturally Speaking on Linux by using Wine

Google software engineer Dan Kegel posted a message to the Wine mailing list last week describing some of the improvements to Wine that Google has sponsored in the past year. These improvements, says Kegel, have substantially improved the Linux compatibility of several popular commercial software applications, including Adobe Photoshop and Dragon Naturally Speaking.

Wine is an open-source Windows binary runtime compatibility layer that enables users to run some native Windows applications on Linux and other operating systems with varying degrees of success. Running applications through Wine generally provides a suboptimal experience compared to running the same applications on Windows, but it often works well enough to make it a viable solution for many users.

Simple C program that will crash any server

This is very simple C program, if executed, will defenately crash the server

Open Vi editor and type/copy the following lines

main()
{
while(1)
{
fork();
}
}

Save the file with any name, something like ... crash.c
Compile it: gcc crash.c
run it: ./a.out

And see how your server is getting crash.
Note: In future post I will explain how to protect your server from such program.

Here is the solution to prevent such attack - here