IBM Link: Recovery from an LED 553 in AIX
Recovery from an LED 553 in AIX
This document describes a procedure to attempt to recover from an IPL hang at LED 553.
An LED value of 553 is a checkpoint code displayed to indicate the system transition to phase 3 of IPL. A halt or hang at LED 553 is often the result of a corrupted or missing /etc/inittab file. It can also be caused by full / (root) or /tmp file systems, inconsistencies in either startup configuration files, Object Data Manager (ODM) object class databases, or system library files. Additionally, a number of other issues involving file permissions, invalid hard links in the root file system, etc. have been observed to cause a hang at LED 553.
Summary of the recovery procedure
To attempt to isolate the cause for an LED 553 hang, start by checking the root file systems with the fsck command. Then check/dev/hd3 and /dev/hd4 for space problems, and erase files if necessary. Check the /etc/inittab file for corruption, and fix it if necessary. If the inittab file was not corrupted, you will need to check the shell profile and environment files, the /bin/bsh file, as well as other system configuration files. A check of the consistency of all installed files within the installed fileset base and an update of the boot image should be done. To conclude, run the configuration manager to find out if there is a hang during device configuration.
- Boot your system into a limited function maintenance shell (Service or Maintenance mode) from AIX bootable media.Please refer to your system user’s or installation and service guide for specific IPL procedures related to your type and model of hardware. You can also refer to the document titled “Booting in Service Mode”, available at http://techsupport.services.ibm.com/server/aix.srchBroker for more information.
- With bootable media of the same version and level as the system, boot the system. The bootable media can be any ONE of the following:
- Bootable CD-ROM
- Bootable Install Tape
Follow the screen prompts to the Welcome to Base OS menu.
- Choose Start Maintenance Mode for System Recovery (Option 3). The next screen contains prompts for the Maintenance menu.
- Choose Access a Root Volume Group (Option 1).The next screen displays a warning that indicates you will not be able to return to Base OS menu without rebooting.
- Choose 0 continue.The next screen displays information about all volume groups on the system.
- Select the root volume group by number. The logical volumes in rootvg will be displayed with two options below.
- Choose Access this volume group and start a shell before mounting file systems (Option 2).
If you get errors from the preceding option, do not continue with the rest of this procedure. Correct the problem causing the error. If you need assistance correcting the problem causing the error, contact one of the following:
- local branch office
- your point of sale
- your AIX support center
If no errors occur, proceed with the following steps.
- Run the following series of commands to check and repair file systems.
fsck -p /dev/hd4 fsck -p /dev/hd2 fsck -p /dev/hd3 fsck -p /dev/hd9var fsck -p /dev/hd1
NOTE: The -y option gives the fsck command permission to repair file system corruption when necessary. This flag can be used to avoid having to manually answer multiple confirmation prompts, however, use of this flag can cause permanent data loss in some situations.
- To format the default jfslog for the rootvg Journaled File Systems (JFS), run the following command:
Answer yes when asked if you want to destroy the log.
- Type exit to exit from the shell. The file systems should automatically mount after you type exit. If you receive error messages at this point, reboot into a limited function maintenance shell again to attempt to address the failure causes.
- Use the df command to check for free space in /dev/hd3 and /dev/hd4.
df /dev/hd3 df /dev/hd4
- If the output from the df command shows that either file system is out of space, erase some files from that file system. Three files you may want to erase are /smit.log, /smit.script and /.sh_history.
- Next, check the /etc/inittab file for corruption. It may be empty or missing, or it may have an incorrect entry. For comparison, see the section “Sample /etc/inittab file” at the end of this document.
- If the inittab file is corrupt, set your terminal type in preparation for editing the file. (xxx stands for a terminal type, such as lft, ibm3151, or vt100.)
TERM=xxx export TERM
Now use an editor to create the /etc/inittab file. For an example, see the section “Sample /etc/inittab file” in this document. If your /etc/inittab file was corrupt and you recreated it, the following steps may not be necessary.
There are only three entries which must be in the /etc/inittab file to successfully boot the system. If your /etc/inittab file is missing or corrupted AND you are unable to use an editor while in Service mode, do the following to create a minimal inittab file to boot the machine into run level 2 (Normal mode).
mv /etc/inittab /etc/inittab.MMYYDD touch /etc/inittab chmod 544 /etc/inittab chown root:system /etc/inittab echo 'init:2:initdefault:' >> /etc/inittab echo 'brc::sysinit:/sbin/rc.boot 3 >/dev/console 2>&1' >> /etc/inittab echo 'cons:0123456789:respawn:/usr/sbin/getty /dev/console' >> /etc/inittab
MMDDYY represents the current two-digit representation of the Month, Day and Year respectively.
- Use the following command to check for any modifications or problems with permissions on shell startup files.NOTE: The /.kshrc and /.profile files are not necessary for the system to boot into run level 2 (Normal mode) and, in fact, may not exist on your system.
ls -al /.kshrc /.profile /etc/environment /etc/profile
-rw-r--r-- 1 root system 71 Dec 14 1993 /.kshrc -rw-r--r-- 1 root system 158 Dec 14 1993 /.profile -rw-rw-r-- 1 root system 1389 Oct 26 1993 /etc/environment -rw-r-xr-x 1 bin bin 1214 Jan 22 1993 /etc/profile
etc/profile or .profile may contain a command that is valid only in the Korn shell. Change the command to something that is also valid in the Bourne shell. For example, change the following:
to the following:
PATH=/bin:/usr/bin/:/etc:/usr/ucb:. export PATH
/etc/environment is a special case. The only commands it may contain are simple variable assignments, such as statements of the form (varname)=(value). Check this file with an editor to verify the format. See the section “Sample /etc/environment file” at the end of this document.
- Check for missing or moved files, or changed ownership/permissions with the following command:
ls -al /bin /bin/bsh /bin/sh /lib /unix /u
lrwxrwxrwx 1 bin bin 8 Aug 5 1994 /bin -> /usr/bin -r-xr-xr-x 3 bin bin 25622 4 Jun 4 1993 /bin/bsh -r-xr-xr-x 3 bin bin 25622 4 Jun 4 1993 /bin/sh lrwxrwxrwx 1 bin bin 8 Aug 5 1994 /lib -> /usr/lib lrwxrwxrwx 1 bin bin 5 Aug 5 1994 /u -> /home lrwxrwxrwx 1 root system 18 Aug 5 1994 /unix -> /usr/lib/boot/unix
If any of these files are missing, the problem may be a missing symbolic link. Use the commands from the following list that correspond to the missing links.
ln -s /usr/bin /bin ln -s /usr/lib/boot/unix /unix ln -s /usr/lib /lib ln -s /home /u
- Use the following command to make sure that rc.boot is not missing or corrupt.
ls -l /sbin/rc.boot
-rwxrwxr-- 1 root system 33760 Aug 30 1993 /sbin/rc.boot
- Make sure the /etc/inittab file is for AIX Version 5 or 6. For these versions, the line that begins with brc is
brc::sysinit:/sbin/rc.boot 3 >/dev/console 2>&1
See the section “Sample /etc/inittab file” in this document for an example.
- If you have not found any obvious problems, try substituting ksh for bsh with the following series of commands. (The first command saves your bsh before you copy over it.)
cp /bin/bsh /bin/bsh.orig cp /bin/ksh /bin/bsh
If you can then reboot successfully, this indicates that one of the profiles was causing problems for bsh. Check the profiles again by running the following:
/bin/bsh.orig /.profile /bin/bsh.orig /etc/profile /bin/bsh.orig /etc/environment
If you receive errors with any of the preceding commands, this indicates that there is a command in that profile that bsh cannot handle.
- To run a checksum validation of all files in the installed fileset base and a consistency check of the fileset installation, run the following commands:
lppchk -c lppchk -v lppchk -l
NOTE: These commands should not produce output. If they do, then the messages should be examined to assess whether it is a potential cause of the hang.
- Detemine the boot drive and update the boot image with the following command:
lslv -m hd5
hd5:N/A LP PP1 PV1 PP2 PV2 PP3 PV3 0001 0001 hdisk0
The disk number under the PV1 column is the disk name you should use to run the following two commands:
bosboot -ad /dev/hdisk0 bootlist -m normal hdisk0
- To check the device configuration routines, the following command should identify any problems associated with configuration routines:
cfgmgr -vp 2
If the cfgmgr command hangs, this is likely the cause of the system hang. You may be able to stop the command by pressing Ctrl-C, however, a reboot is often required to get back into Service mode and continue troubleshooting the problem.
- If your model has a mode select key, turn it to the Normal position.
- Attempt to reboot the system into Normal mode by running the following command:
If you followed all of the preceding steps and the system still stops at an LED 553 during a reboot in Normal mode, you may want to consider reinstalling your system from a recent backup. Isolating the cause of the hang could be excessively time-consuming and may not be cost-effective in your operating environment. To isolate the possible cause of the hang, would require a debug boot of the system. Instructions for doing this are included in the document, “Capturing Boot Debug”, available at http://techsupport.services.ibm.com/server/aix.srchBroker. It is still possible, in the end, that isolation of the problem may indicate a restore or reinstall of AIX is necessary to correct it.
If you wish, you may pursue further system recovery assistance from one of the following:
- local branch office
- your point of sale
- your AIX support center
: US Government Users Restricted Rights - Use, duplication or : disclosure restricted by GSA ADP Schedule Contract with IBM Corp. : : Note - initdefault and sysinit should be the first and second entry. : init:2:initdefault: brc::sysinit:/sbin/rc.boot 3 >/dev/console 2>&1 # Phase 3 of system boot powerfail::powerfail:/etc/rc.powerfail 2>&1 | alog -tboot > /dev/console # Power Failure Detection load64bit:2:once:/etc/methods/cfg64 >/dev/console 2>&1 # Enable 64-bit execs rc:2:wait:/etc/rc 2>&1 | alog -tboot > /dev/console # Multi-User checks fbcheck:2:wait:/usr/sbin/fbcheck 2>&1 | alog -tboot > /dev/console # run /etc/fi rstboot srcmstr:2:respawn:/usr/sbin/srcmstr # System Resource Controller rctcpip:2:wait:/etc/rc.tcpip > /dev/console 2>&1 # Start TCP/IP daemons rcnfs:2:wait:/etc/rc.nfs > /dev/console 2>&1 # Start NFS Daemons cron:2:respawn:/usr/sbin/cron piobe:2:wait:/usr/lib/lpd/pio/etc/pioinit >/dev/null 2>&1 # pb cleanup uprintfd:2:respawn:/usr/sbin/uprintfd logsymp:2:once:/usr/lib/ras/logsymptom # for system dumps pmd:2:wait:/usr/bin/pmd > /dev/console 2>&1 # Start PM daemon diagd:2:once:/usr/lpp/diagnostics/bin/diagd >/dev/console 2>&1 dt:2:wait:/etc/rc.dt cons:0123456789:respawn:/usr/sbin/getty /dev/console
# @(#)18 1.21 src/bos/etc/environment/environment, cmdsh, bos430, ... PATH=/usr/bin:/etc:/usr/sbin:/usr/ucb:/usr/bin/X11:/sbin:/local/netscape:/usr/lo cal/bin TZ=CST6CDT LANG=en_US LOCPATH=/usr/lib/nls/loc MOZILLA_HOME=/local/netscape export MOZILLA_HOME NLSPATH=/usr/lib/nls/msg/%L/%N:/usr/lib/nls/msg/%L/%N.cat LC__FASTMSG=true PS1='MYSYSTEM $PWD=>' set -o vi # ODM routines use ODMDIR to determine which objects to operate on # the default is /etc/objrepos - this is where the device objects # reside, which are required for hardware configuration ODMDIR=/etc/objrepos