Skip to main content

What are logical volumes?

26.What are logical volumes?
Ans.
1. Logical volume manager (LVM) enables you to be much more flexible with your disk usage than you can be with conventional old-style file partitions.

2. Normally if we create a partition we have to keep the partition at that size indefinitely.

3. For example, if our system logs have grown immensely, and we ran out of space on ‘/var’ partition, increasing a partition size without LVM is a big pain.

4. With LVM we can add another disk, create a physical volume to the volume group that contains the /var partition.

5. Then we can use the LVM file system resizing tool to increase the file system size to match the new partition size.

6. We can use a file system creation tool such as fdisk to create a file system on logical volume.

7. Basic syntax for using ‘lvm’ command is :
lvm<command> file
We can obtain complete listing of commands by entering ‘lvm help’ at command prompt.

8. To get a list of logical volumes on your system, enter ‘lvm lvdisply’ in terminal prompt.

Comments

Popular posts from this blog

Explain the tools used to monitor system security.

12.Explain the tools used to monitor system security. Ans. 1. People who, for purpose of larceny or to amuse themselves, like to break into computers, they are called ‘crackers’. 2. If there is a vulnerability in a system they will find it and use it against you. 3. Preventing use of your machine for nefarious purpose and guarding against intrusion are, in the end, your responsibility alone. 4. Red hat equips you with tools to detect and deal with unauthorised access of many kinds. 5. You need to configure those tools and understand how to sense the warning they provide. 6. Fortunately Linux is development community is quick to find potential exploits and to create ways of slamming the doors before crackers can enter in your system. 7. Red hat is careful enough to making available new, patched version in which potential exploits have been found. 8. You should make sure to download and install the repaired package. 9. This line of defence...

Explain the file systems supported by Linux.

21.Explain the file systems supported by Linux. Ans. 1. Linux can read/write to several file system that originated with other operating system much different from Linux. 2. One reason that Linux supports so many file systems is the design of its virtual file system (VFS) layer, its provides a fairly universal forms of file support, file systems supported by Linux are as follows: 3. ext3: • Ext3 stands for third extended file system. • Starting from Linux Kernel 2.4.15 ext3 was available. • The main benefit of ext3 is that it allows journaling. • Journaling has a dedicated area in the file system, where all the changes are tracked. • When the system crashes, the possibility of file system corruption is less because of journaling. (If no journaling, then fsck command (file system consistency check) is used to check for the corrupted file and to repair that file). • ext3 keeps a record of uncommitted file transactions and applies only those transactions when the sy...

Explain the backing up and restoring files in Linux.

9.Explain the backing up and restoring files in Linux. Ans. 1. Backing-up and restoring files is done only by system administrator. 2. Because of built-in features, Linux doesn’t allow users to back-up their own files to removable disks. 3. It’s not enough to know that performing backup is your job, you need to formulate a strategy to making sure your system is not vulnerable to sudden disastrous disruptions. 4. If you have a high capacity tape drive and several good set of restore disks you can take backup every few days. 5. If you are managing a system with scores of users, you might find it more sensible to back up accounts and system configurations. 6. Only you can decide ‘what’ to backup, you need to decide ‘how frequently’ to perform backups, whether to maintain series of incremental backup. 7. You should maintain perfect backups without ever needing to restore to them, this means encouraging users to keep multiple copies of their important files in their ho...