Linux as the Backbone of Kubernetes and Hadoop Ecosystems

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1. ext4 file system is introduced. 2. xen is removed and kernel virtualization machine (KVM) is introduced. 3. neat command is removed. 4. portmap service is removed. 5. iscsi is introduced, which supports for SAN. 6. rpmbuild is available, which is used to create our own rpms. 7. File encyption is added. 8. palimpsest is available for disk management. 9. Virtual machine will run only on 64bit processors. 10. postfix service is recommended instead of sendmail service

Linux User Disk Quota Implementation What is disk quota? Ans :  Disk quota is  restricting the  disk-space   usage to the users . We have to remember one  thing when we are dealing with disk quota i.e. Disk Quota can be applied only on  disks/partitions  not on  files and folders . how we can implement disk quota? Disk quota can be implemented in   two   ways a.   On   INODE b.   On   BLOCK What is an INODE? Ans :   In Linux every object is consider as   file , every file will be having an   inode number   associated and this is very much easy for computer to recognize where the file is located. Inode   stands for   Index Node , and is the focus of all file activities in the UNIX file-system. Each file has one inode that defines the file’s type (regular, directory, device etc), the location on disk, The size of the file, Access permissions, Access times. Note ...

Configure Linux samba server step by step guide example and implementation Exam question There are mixed lots of System running on Linux and Windows OS. Some users are working on Windows Operating System. There is a /data directory on Linux server should make available on windows to only sadeek should have right to connect with samba server . Configure to make available. Configure samba server How to make a Samba Server on RHEL6 Install Samba packages in your machine by yum command: [root@sadeek~]$ yum install samba* -y Open Samba's configuration file: [root@sadeek ~]$ vi /etc/samba/smb.conf # at line 58 add the following unix charset = UTF-8 dos charset = CP932 # at line 75 change to the windows workgroup. workgroup =  WORKGROUP # at line 81 uncomment and change the ip addresses. hosts allow = 127. 192.168.  (127 is for local host and your machine virtual ip if you are using a VM). # at line 102 chang...

SSH is often used to login from one machine to another machine, There are number of methods to achieve this but mostly in every method it requires authentication..... It also does require authentication but for one time only i.e. for the first time you need to do a setup and for rest of the times when you will try to login via ssh it will not ask for any password. you just need to generate your own personal set of private/public key pair. ssh-keygen is used to generate that key pair. How to generate public/private key root@server:/other_part# ssh-keygen -t rsa Press  (enter) generating public/private rsa key pair. Enter file in which to save the key (/root/.ssh/id_rsa):   (save your default  on default location) Enter passphrase (empty for no passphrase): Enter same passphrase again: Your identification has been saved in /root/.ssh/id_rsa.  (enter) Your public key has been saved in /root/.ssh/id_rsa.pub.   (enter) The key finger...

Press the power button on your system, and after few moments you see the Linux login prompt. Have you ever wondered what happens behind the scenes from the time you press the power button until the Linux login prompt appears? The following are the 6 high level stages of a typical Linux boot process. 1. BIOS BIOS stands for Basic Input/Output System Performs some system integrity checks Searches, loads, and executes the boot loader program. It looks for boot loader in floppy, cd-rom, or hard drive. You can press a key (typically F2 of ESC, but it depends on your system) during the BIOS startup to change the boot sequence. Once the boot loader program is detected and loaded into the memory, BIOS gives the control to it. So, in simple terms BIOS loads and executes the MBR boot loader. 2. MBR MBR stands for Master Boot Record. It is located in the 1st sector of the bootable disk. Typically /dev/hda, or /dev/sda MBR is less than 512 bytes in size. This h...

badblocks Used to search a disk or partition for badblocks. cfdisk Similar to fdisk but with a nicer interface. debugfs Allows direct access to filesystems data structure. df Shows the disk free space on one or more filesystems. dosfsck Check and repair MS-Dos filesystems. du Shows how much disk space a directory and all its files contain. dump Used to back up an ext2 filesystem. Complement is restore. dumpe2fs Dump filesystem superblock and blocks group information. Ex: dumpe2fs /dev/hda2 e2fsck Check a Linux second extended filesystem. e2label Change the label on an ext2 filesystem. exportfs Used to set up filesystems to export for nfs (network file sharing). fdisk Used to fix or create partitions on a hard drive. fdformat Formats a floppy disk. fsck Used to add new blocks to a filesystem. Must not be run on a mounted file system. hdparm Get/set hard disk geometry parameters, cylinders, heads, sectors. mkfs Initializes a Linux filesystem. This is a...

profile System wide environment and startup script program. /dev/MAKEDEV The /dev/MAKEDEV file is a script written by the system administrator that creates local only device files or links such as device files for a non-standard device driver. /etc/aliases Where the user's name is matched to a nickname for e-mail. /etc/bootptab The configuration for the BOOTP server daemon. /etc/crontab Lists commands and times to run them for the cron deamon. /etc/dhcpd.conf The configuration file for the DHCP server daemon. /etc/ethers File for RARP mapping from hardware addresses to IP addresses. See the man page ethers(5). /etc/exports The file describing exported filesystems for NFS services. /etc/fdprm The floppy disk parameter table. Describes the formats of different floppy disks. Used by setfdprm. /etc/filesystems Can be used to set the filesystem probe order when filesystems are mounted with the auto option. The nodev parameter is specified for filesystems tha...

#########RHEL4 and RHEL 5 ######################## XEN, YUM and improved SELinux all the features updated with better options Better GUI support then RHEL4 YUM over RPM package management IPTables and SELinux for more secure environment ext2 & ext3 file system In RHEL 4 SELinux Block only 13 services, But on RHEL 5 SElinux Block 80 services  ############################################### Difference between RHEL 4 and RHEL 5 : 1) In RHEL 4 SELinux Block only 13 services, But on RHEL 5 SElinux Block 80 services. 2) RHEL 4 have ext2 filesystem, but RHEL 5 we have ext3 filesystem that support Journal. 3) RHEL 4 have no virtualization Feature, but in RHEL 5 we have virtualization with Hypervisor-V. 4) In RHEL 4 we have no Yum, But in RHEL 5 we have Yum available. #####################################################

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