System Adm » hardware

Updating partition table in Linux

Lincoln Zuljewic Silva — Mon, 15 Mar 2010 14:53:16 +0000

When you use the "fdisk" to handle the partitions of a disk, depending on the disc, the "fdisk" will bring the following message:

WARNING: Re-reading the partition table failed with error 22: Invalid argument. The kernel still uses the old table. The new table will be used at the next reboot. Syncing disks.

No, you do not have to restart the server for the changes are applied, simply use the following command (example):
kpartx -a /dev/sda

This will re-read the partition table on /dev/sda and create the mapping of the system partitions (/dev/sda1, /dev/sda2, etc).

Physical memory in AIX

Lincoln Zuljewic Silva — Thu, 18 Feb 2010 11:56:21 +0000

To check the amount of physical RAM that a AIX Server has, you can use the following commands:

# lsattr -El sys0 | grep realmem realmem 16121856 Amount of usable physical memory in Kbytes

or

# lsattr -El mem0 goodsize 15744 Amount of usable physical memory in Mbytes False size 15744 Total amount of physical memory in Mbytes False

# prtconf|grep "Memory Size" Memory Size: 15744 MB Good Memory Size: 15744 MB

Hardware specification in HP-UX

Lincoln Zuljewic Silva — Tue, 26 May 2009 13:48:00 +0000

You can use the following command to check the HP-UP hardware (like CPU and memory):

# hpuxhost@root:/root # print_manifest |more System Information


	Your Hewlett-Packard computer has software installed and

	configured as follows.
	The system was created July 04, 2007, 11:53:28 EDT.
	It was created with Ignite-UX revision C.6.10.97.
	-------------------------------------------------------------

	NOTE: You should retain this information for future reference.

	-------------------------------------------------------------

System Hardware Model: 9000/800/SD32A Main Memory: 65005 MB Processors: 32 Proccesor(0) Speed: 1000 MHz Proccesor(1) Speed: 1000 MHz Proccesor(2) Speed: 1000 MHz Proccesor(3) Speed: 1000 MHz Proccesor(4) Speed: 1000 MHz Proccesor(5) Speed: 1000 MHz Proccesor(6) Speed: 1000 MHz Proccesor(7) Speed: 1000 MHz Proccesor(8) Speed: 1000 MHz Proccesor(9) Speed: 1000 MHz Proccesor(10) Speed: 1000 MHz Proccesor(11) Speed: 1000 MHz Proccesor(12) Speed: 1000 MHz Proccesor(13) Speed: 1000 MHz Proccesor(14) Speed: 1000 MHz Proccesor(15) Speed: 1000 MHz Proccesor(16) Speed: 1000 MHz Proccesor(17) Speed: 1000 MHz Proccesor(18) Speed: 1000 MHz Proccesor(19) Speed: 1000 MHz Proccesor(20) Speed: 1000 MHz Proccesor(21) Speed: 1000 MHz Proccesor(22) Speed: 1000 MHz Proccesor(23) Speed: 1000 MHz Proccesor(24) Speed: 1000 MHz Proccesor(25) Speed: 1000 MHz Proccesor(26) Speed: 1000 MHz Proccesor(27) Speed: 1000 MHz Proccesor(28) Speed: 1000 MHz Proccesor(29) Speed: 1000 MHz Proccesor(30) Speed: 1000 MHz Proccesor(31) Speed: 1000 MHz (...) Many other HW information above

Recovering corrupted lvol on HP-UX

Lincoln Zuljewic Silva — Thu, 14 May 2009 19:32:34 +0000

Sometimes you can get the following error while try to access a directory in HP-UX:

# cd /DATA sh: /DATA: The specified directory is not valid.

This error is caused because the file system is corrupted and you need run fsck on it.

First of all, umount the FS:

# umount /DATA

And them, run the fsck:

# fsck -y -o full /dev/vgLOG/lvol1on clear? (ynq)y UX:vxfs fsck: WARNING: V-3-20836: file system had I/O error(s) on meta-data. log replay in progress pass0 - checking structural files pass1 - checking inode sanity and blocks fileset 999 primary-ilist inode 177502 marked bad, allocation flags (0x0001) fileset 999 primary-ilist inode 177502 has invalid number of blocks (7309) fileset 999 primary-ilist inode 177502 has invalid block map fileset 999 primary-ilist inode 177502 failed validation clear? (ynq)y fileset 999 primary-ilist inode 177859 marked bad, allocation flags (0x0001) fileset 999 primary-ilist inode 177859 has invalid number of blocks (24850) fileset 999 primary-ilist inode 177859 has invalid block map fileset 999 primary-ilist inode 177859 failed validation clear? (ynq)y fileset 999 primary-ilist inode 178243 marked bad, allocation flags (0x0001) fileset 999 primary-ilist inode 178243 has invalid number of blocks (6417) fileset 999 primary-ilist inode 178243 has invalid block map fileset 999 primary-ilist inode 178243 failed validation clear? (ynq)y fileset 999 primary-ilist inode 178793 marked bad, allocation flags (0x0001) fileset 999 primary-ilist inode 178793 failed validation clear? (ynq)y pass2 - checking directory linkage pass3 - checking reference counts pass4 - checking resource maps fileset 999 au 2 imap incorrect - fix (ynq)y fileset 999 au 2 iemap incorrect - fix (ynq)y au 42 emap incorrect - fix? (ynq)y au 42 summary incorrect - fix? (ynq)y au 59 emap incorrect - fix? (ynq)y au 59 summary incorrect - fix? (ynq)y au 60 emap incorrect - fix? (ynq)y au 60 summary incorrect - fix? (ynq)y au 61 emap incorrect - fix? (ynq)y au 61 summary incorrect - fix? (ynq)y au 62 emap incorrect - fix? (ynq)y au 62 summary incorrect - fix? (ynq)y au 63 emap incorrect - fix? (ynq)y au 63 summary incorrect - fix? (ynq)y fileset 999 iau 2 summary incorrect - fix? (ynq)y free block count incorrect 2153192 expected 2202289 fix? (ynq)y free extent vector incorrect fix? (ynq)y OK to clear log? (ynq)y set state to CLEAN? (ynq)y

After that, you can mount the FS again.

# umount /DATA