Linux Failure handling: Disk resource exhaustion failure

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cause of failure: disk space has been depleted by large amounts of data, although there is still space available, but the number of files I node has also been exhausted

It is obvious that when a filesystem runs out of disk space, it will not be possible to continue creating new file data in that partition, causing the failure to occur, for example, when the root partition " / "When you run out of disk space, it can cause some programs and even the entire system to not start or run properly because some temporary files will not be built

Unable to boot into the root partition when disk space is low Linux system, you can use the RHEL 5 installation CD into first aid mode, transfer or clean up files that occupy a lot of space in the root partition, use DD command can simulate a root partition exhaustion failure, for example: Execute " DD If=/dev/zero of=/somefile bs=1m count=999999 "

in addition, in each of the ext3 The number of files that can be used in the file system ( corresponds to number of I nodes ) is also limited, when a file system is formatted, its I The number of nodes, or the number of files, is fixed, if the user creates a huge amount of small files in the partition (exhausted I node), this situation may occur, although there is still a large amount of remaining disk space in the partition, but the user is no longer able to create new files.

one. simulation i

(1) Create a new 32m size ext3 file system, mount it to /date directory, and use with " -i df command confirms that the file system is i node usage.

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(2) refer to the following to write a test program, run the program can be exhausted /DEV/SDB1 all available in the partition I node, ( 10029 )

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(3) Run the test program sh killinode.sh &

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(4) df-i/date Confirm I node Occupancy

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( 5 ) When I a new file cannot be created after the node is exhausted

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( 6 ) df-h t/date View disk space usage

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( 7 ) Fix I node several faults, understanding I after the node exhausts the root knot of the failure, the problem is resolved, just to find out that the partition occupies a large number of I node's small files, and run transfer or delete to

method One: rm-rf/date/file*

Method Two: Vim Jiaoben

A= ' Find/date-type f-a-empty '

For B in $a

RM-RF $b

Done

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Linux Failure handling: Disk resource exhaustion failure