1. File System Management (Real Time)

1. File System Management

File System issues are not a regular task.

Basic commands:

# uname –a                              To display the OS name, version, kernel version

# isainfo –b                             Display the kernel bit

# format                                  To find the available disk

# newfs –N                             Display the super block & primary block

Last + found                           consist of inode, data block information

# ls –s *                                   List all the details of files & directories

                                                (for touch 0Mb, for cat 2 blocks)

Q: How to check which file occupying more memory in File system?

A:

# cd /sai                       /sai is the mount point

# du –sh * | sort –nr                // displays the files occupying more memory

Q: Can we increase the file system in Solaris?

A: Generally we cannot increase the File System, but we can increase the File system if continuous cylinders available.

# growfs –M /sai /dev/rdsk/c0d0s6

# df –h /sai

Q: Can we decrease the File System?

A: No way, not possible

Note: to over come this problem SVM (Solaris Volume Manager) use.

How many are using the File System?

# cd /sai

# fuser –u /sai                          // to display how many users using File System

To check the minfree:

#fstyp –v /dev/rdsk/c0d0s0 | grep –i minfree

We can write the script for repeated loop of status:

# while true

> do

> fstyp –v /dev/rdsk/c0d0s0 |grep –i  minfree

> done

To increase the minfree:

# tunefs –m 20 /dev/rdsk/c0d0s0

To decrease the minfree:

# tunefs –m 10 /dev/rdsk/c0d0s0

Issue 1:

If file system exceeds the threshold value then ticket will generate automatically.

A:To resolve this

Check out more size files in File System

Compress the files or delete the old files, if it is so important consult the clients then delete.

Copy /keep the data:

# cp –r /usr/* .

To see old files;

# ls –ltr

To gip:

# gzip aa

To unzip:

# gunzip aa.gz

^*** To find top 10 files occupied more size:

# find . –xdev –type f –ls | sort –nr +6|head -10

^*** To find top 20 files occupied more size:

# find . –xdev –type f –ls | sort –nr +6|head -20

To move the data:

# mv /etc/aa /opt               move /aa to /opt

Issue 2:

If inodes are corrupted (some times file system also will not work)

A: To resolve:

I will ask the backup team to take backup of file system, & restore it freshly.

Issue 3:

Suppose my File System is 2 GB, its usage is 1GB, but it is showing 100%. Actually it has to show 50%.

A:To resolve:

Simply I unmount & mount the filesystem

Or

If it is not release the space, I will reboot. Then it will show 50%.

Issue 4:

User can not accessing the file system

A: To resolve:

Check out the file permissions, and give the proper permissions to that file.

# mount: mount file system from mnttab

# mountall: mount all file system from vfstab