System Adm

AIX and user access denied

Lincoln Zuljewic Silva — Wed, 19 May 2010 20:11:00 +0000

AIX has a security feature named unsuccessful_login_count (/etc/security/lastlog) . It is an user account feature that count the number of unsuccessful login attempts and it works conjunction with the user's loginretries (/etc/security/user) attribute.

So, if you configure the loginretries=5, the user will not be able to log in after 5 retries. To enable the login again, you should reset the unsuccessful_login_count parameter by editing the file /etc/security/lastlog or with the following command:

# chsec -f /etc/security/lastlog -a unsuccessful_login_count=0 -s foobar

You can identify this problem by the following message in syslog:

May 19 15:42:41 aixbox auth|security:info sshd[7884888]: Login restricted for foobar: 3004-303 There have been too many unsuccessful login attempts; please see \tthe system administrator.

Change user settings and password attributes in AIX

Lincoln Zuljewic Silva — Tue, 11 May 2010 14:03:53 +0000

To change some user and password settings in AIX, you should use the command "chuser". Follow some available parameters:

- loginretries -> number of login failures before lock the account.
- maxage -> maximum age of a password (in weeks)
- gecos -> general information about the user.
- groups
- home
- minlen -> minimum password length
- pgrp -> primary group

Example:
# chuser loginretries='0' maxage='0' gecos='User Foo Bar' groups='group1,group2,group3' home='/home/foobar' minlen='7' pgrp='groupX'

Unlock user account in AIX

Lincoln Zuljewic Silva — Tue, 11 May 2010 13:38:49 +0000

To unlock an user account in AIX, you should use the following command:

# chuser account_locked='true'

Lock user account in AIX

Lincoln Zuljewic Silva — Tue, 11 May 2010 13:37:33 +0000

To lock an user account in AIX, you should use the following command:

# chuser account_locked='false'

Increase lvol size in HP-UX

Lincoln Zuljewic Silva — Fri, 07 May 2010 21:11:21 +0000

Let’s assume that you want to increase 1Gb of the /dev/MyVG /lvol1 device (mounted as /filesystem):
# bdf /filesystem Filesystem kbytes used avail %used Mounted on /dev/ MyVG /lvol1 573440000 533892407 37080557 94% /filesystem
The actual size is 573440000 Kb (573 Gb) and you will increase it to 574440000 Kb (574 Gb).

- Check if there is available space in the Volume Group:
# vgdisplay MyVG --- Volume groups --- VG Name /dev/MyVG VG Write Access read/write VG Status available Max LV 255 Cur LV 1 Open LV 1 Max PV 100 Cur PV 17 Act PV 17 Max PE per PV 15000 VGDA 34 PE Size (Mbytes) 16 Total PE 36907 Alloc PE 35000 Free PE 1907 Total PVG 1 Total Spare PVs 0 Total Spare PVs in use 0

Note the “Free PE” and “PE Size (Mbytes)”. It say that you has 30512 Mb (30Gb) available in MyVG (Free PE * PE Size).

- Increase the lvol:
# lvextend -L 574440 /dev/MyVG/lvol1 * the syntax is: lvexten -L

- Now, increase the filesystem:
# fsadm -b 574440m /filesystem * the syntax is: fsadm –b

Changing the HP-UX hostname

Lincoln Zuljewic Silva — Fri, 07 May 2010 18:08:34 +0000

To change the hostname in HP-UX:

- Edit the file "/etc/rc.config.d/netconf"
# /etc/rc.config.d/netconf
- Look for the line that starts with HOSTNAME and change the hostname, example:
HOSTNAME="mylittleserver"
- Now, apply the change:
# /sbin/init.d/hostname start

Rename a Super Dome Partition

Lincoln Zuljewic Silva — Fri, 23 Apr 2010 14:31:40 +0000

To rename a Super Dome Partition (for example change the name that is showed in the MP console menu), do the following:

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

Glance shortcuts

Lincoln Zuljewic Silva — Thu, 04 Feb 2010 13:00:24 +0000

To use the buttons at the bottom of the glance, you should do an "export TERM=dtterm".

After that, you will be able to use:
F1 for ProcList F2 for CPU Rpt F3 for Mem Rpt F4 for Disk Rpt F5 for NextKeys F6 for SlctProc F7 for Help F8 for Exit

Control agent problem (OVO)

Lincoln Zuljewic Silva — Fri, 08 Jan 2010 22:32:24 +0000

Sometimes the OVO agent stops communicating with the OVO Server.
Control agent on nodeHOST isn't accessible. (OpC40-405) Network communication problem: Could not obtain endpoint information from node ncadg_ip_udp:10.0.0.10[]. (OpC40-399)
To reestablish the communication, you should restart it:

To stop, use the command:
# /opt/OV/bin/OpC/opcagt -stop

Check if it is stopped:
# /opt/OV/bin/OpC/opcagt -status ITO Managed Node status : ------------------------- Control Agent /opt/OV/bin/OpC/opcctla (3818) is running Message Agent /opt/OV/bin/OpC/opcmsga (3819) is running Subagent 1: Action Agent /opt/OV/bin/OpC/opcacta (3820) is running Logfile Encapsulator /opt/OV/bin/OpC/opcle (3821) is running Monitor Agent /opt/OV/bin/OpC/opcmona (3822) is running Message Interceptor /opt/OV/bin/OpC/opcmsgi (3823) is running

Attention: the "Control Agent" may not stop, you can kill it with a "kill -9 PID"

To start, use the command:
# /opt/OV/bin/OpC/opcagt -start

Check powerpath links in HP-UX

Lincoln Zuljewic Silva — Tue, 22 Dec 2009 20:22:43 +0000

To check if the powerpath links are up in HP-UX, you can use the following command:

# powermt display dev=all

When Glance stop working

Lincoln Zuljewic Silva — Sun, 06 Dec 2009 20:41:39 +0000

Sometimes glance (performance monitor for HP-UX) can crash (before crash, it will return 0% of CPU, Disk and networking) working with the following error:
GlancePlus fatal error. == Fatal Nums Error == C.04.50.57 02/10/07 == User: root/6pts/6(/dev/pts/6) Date: Sun Dec 6 15:52:12 File: /crm/numsVob/hp/11.0/nums.C Line: 485 Product id: Glance System: server B.11.11 9000/800 Errno: 0 (Error 0) Connection to midaemon lost -- check midaemon process and status.mi == End of Error Msg =============================

To solve it, you should:

Stop MWA:
# mwa stop

Remove all files (including the hidden ones) from /var/opt/perf/datafiles:
# rm -rf /var/opt/perf/datafiles/* rm -rf /var/opt/perf/datafiles/.*

Check if midaemon and ttd are stopped:
# mwa status

If midaemon and ttd didn’t stop, force stops them with the command kill (the PID was returned by the command ‘mwa status’).

Now, start MWA again:
# mwa start

Disable file size limit in AIX

Lincoln Zuljewic Silva — Fri, 04 Dec 2009 11:58:48 +0000

By default, if you try do copy/create a file larger than 2Gb in AIX, you will get a “file too large” message. That happen because AIX have a default limit of 2Gb for files.

To disable (or increase) this limit, edit /etc/security/limits and change the parameter fsize to “-1” or whatever value you want.

You can change it in “default” to apply to all users or change it to a specific user.

Remember that the file system should be JFS2.

Working with “SVC”

Lincoln Zuljewic Silva — Wed, 02 Dec 2009 12:29:40 +0000

Follow useful commands to work with “SVC” in Solaris:

More option can be found at “man svcadm”
# svcs -a -> list all installed services.
# svcadm disable SERVICE -> disable a service. if you use “svcadm disable -t SERVICE”, the service will be disabled only until the next reboot. You can use this commando to stop a service.
# svcadm enable SERVICE -> enable a service. If you use “svcadm enable -t SERVICE”, the service will not be enabled automatically on reboot.
# svcadm restart SERVICE -> restart a service.
# svcadm reload SERVICE -> reload the configuration file.

More options can be found at “man svcadm”

Creating an user on AIX

Lincoln Zuljewic Silva — Tue, 01 Dec 2009 11:33:12 +0000

Creating an user on AIX

On AIX, you can use the following commands to create an user
# mkuser pgrp='primary group' groups='other groups' home='home directory' shell='/usr/bin/ksh' gecos='GECOS' USERNAME

Forcing an user changing the password on AIX

Lincoln Zuljewic Silva — Mon, 30 Nov 2009 21:33:25 +0000

Forcing an user changing the password on AIX

On AIX, you can use the following commands to unlock na user and force it to change it’s password on first logon:
# pwdadm -f ADMCHG USER

Lock an user account in HP-UX

Lincoln Zuljewic Silva — Thu, 24 Sep 2009 17:45:17 +0000

To lock an user account in HP-UX, you can use the following command:

# /usr/lbin/modprpw -m alock=YES USER

Martian Friend

Lincoln Zuljewic Silva — Tue, 15 Sep 2009 16:59:06 +0000

You may find some weird messages indications in your syslog telling you something like “martian source” like the followings:

When a host needs send a package to another host, it can define the route on the network or use the default route. Those “source routed packages” are identified in Linux as martian packages. You can configure your Linux log/do not log those packages:

# echo 0 > /proc/sys/net/ipv4/conf/*/log_martians #do not log

Merge many depots

Lincoln Zuljewic Silva — Tue, 25 Aug 2009 17:58:23 +0000

When you have many depot files, you can create a single big depot and install it instead of install one by one. Let’s assume that you need install the following depots, and they are all located in the directory /tmp/install/depots:

autoconf-2.64-hppa-11.11.depot bison-2.4.1-hppa-11.11.depot gawk-3.1.7-hppa-11.11.depot sed-4.2.1-hppa-11.11.depot tcltk-8.5.7-hppa-11.11.depot texinfo-4.13-hppa-11.11.depot zip-3.0-hppa-11.11.depot

To create a single depot, run the follow commands:
# cd /tmp/install/ for i in `ls depots/*.depot` ;do swcopy -s /tmp/install/$i \* @/tmp/install/big;done

Now, to install it, you can use:
# swinstall -s /tmp/install/big