This document describes what happens during the time that LED 581 is shown during boot up and what may cause an indefinite hang on LED 581. This document applies to AIX Version 4.
LED 581 is shown during the time that the Configuration Manager (/usr/sbin/cfgmgr -s) configures TCP/IP and runs /etc/rc.net to do specific adapter/interface/host name configuration.
Much of what happens during this time depends on factors such as access to a DNS, network traffic, valid network addresses, network access, network hardware/microcode, and the number and type of adapter/interfaces being configured. TCP/IP, over some interfaces (token-ring, for example), will wait for replies. If there are no replies, it will eventually timeout on the attempt and mark the interface as down. Nevertheless, this will take some time, possibly between three to ten minutes, or may hang indefinitely.
Most of the time LED 581 is caused by the DNS client not being able to resolve loopback correctly. This is often caused by a misconfigured or unreachable DNS server. This can be easily solved by resolving loopback locally using the /etc/netsvc.conf file, which dictates the order of name resolution.
mv /etc/netsvc.conf /etc/netsvc.conf.saveme
NOTE: This file might not exist. If it does not exist, create it.
Search for the loopback line and make sure its correct, it should look like the following.
127.0.0.1 loopback localhost
Add the following according to your AIX level and save the file.
mv /etc/resolv.conf /etc/resolv.conf.saveme
NOTE: This file should exist only if you are using DNS for name resolution.
mv /etc/rc.net /etc/rc.net.saveme
chmod 755 /etc/rc.net
Comment out the following 3 lines in /etc/inittab:
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 dt:2:wait:/etc/rc.dt
Also comment out all other lines which depend on TCP/IP being started.
NOTE: Commenting out in /etc/inittab is done with a colon (:) in front of the line.
Boot back up in multiuser mode. The machine should come up. After system is back up in multiuser, enter the following commands:
mv /etc/rc.net.saveme /etc/rc.net
You should see output similar to the following:
Destination Gateway Flags Refs Use If PMTU Exp Groups default 18.104.22.168 UG 3 79448 tr0 - -
From this we see that this machine's default gateway is 22.214.171.124. Make sure you can ping your own default gateway, if it exists.
You should see information similar to the following:
domain austin.ibm.com nameserver 126.96.36.199
Try to ping your nameserver, if you use one.
If all ping tests pass, then see if you can telnet to loopback.
Enter the following:
mv /etc/resolv.conf.saveme /etc/resolv.conf
If everything checks out then uncomment the lines (rcnfs, rctcpip, rc.dt) in /etc/inittab that start TCP/IP, NFS, and the Common Desktop Environment (CDE).
[ Doc Ref: 90605189614752 Publish Date: Jan. 31, 2001 4FAX Ref: 2424 ]