Basic Setup - what to do after AIX is installed?
So you have just installed AIX and want to know what to do next. Here is my list of tasks and what needs to be done next. If any item is missing please add it - that is what a Wiki is all about.
After the AIX installation it takes you through the Install Assist feature. Many people prefer to get out of this "boxed in" menu and quit out of it. But it is still available for you to at any time.
On the command line as the root user type: install_assist
You will see the following list of tasks, which are a pretty good start:
- Set Date and Time
- Set root Password
- Configure Network Communications
- Install Software Applications
Time, Date and Time Zone
It is easy to overlook setting up the time, date and timezone, but many things rely on having these values at least roughly correct.
You may also want to set up a time server so the time stays correct.
| Task (as root user) |
Command |
| Setting the time and date |
smitty date |
| Setting the Time Zone |
smitty chtz |
Set root Password.
If you use no root password, a simple guessable root password or a common root password on all machines then you have no security and deserve the massive problems you may one day suffer as a consequence and then getting sacked - phew! It is good to get that off my chest.
| Task (as root user) |
Command |
| Set root password |
passwd |
Find out what you have and are all the parts you expect online?
If this machine is new or a newly created logical partition (LPAR) then you should know what resources should be in the machine from one of the following:
- the parts list ordered from IBM or and IBM Business Partner
- looking inside the machine for disks, RAM, adapters etc. and drawing up a list
- checking the LPAR configuration on the Hardware management Console (HMC)
- checking the LPAR configuration on the Integrated Virtualization manager web interface (IVM).
You should then check that all the parts and resources are actually available and visible to AIX.
| Task (as root user) |
Command |
| List configuration and components |
lsconf |
- You will need to pipe the output through pg or more as it is a long list.
You should check that every component is present and that you understand what each component on the output is.
Particularly important is to understand the Ethernet ports so that you know which physical port on the machine is en0 so that you can connect the first Ethernet cable to the correct port.
The first part of the report is particularly useful. For example, on my machines
| Resource |
Details |
| System Model |
IBM,9124-720 |
| Machine Serial Number |
(deleted) |
| Processor Type |
PowerPC_POWER5 |
| Number Of Processors |
2 |
| Processor Clock Speed |
1654 MHz |
| CPU Type |
64-bit |
| Kernel Type |
64-bit |
| LPAR Info |
5 IBM_VIO_Server |
| Memory Size |
2048 MB |
| Good Memory Size |
2048 MB |
| Platform Firmware level |
Not Available |
| Firmware Version |
IBM,SF235_152 |
| Console Login |
enable |
| Auto Restart |
true |
| Full Core |
false |
Checks:
- This immediately let me check that the machine type, number of CPUs, the MHz rating and memory configuration are all correct and working.
- The 64 bit kernel is enabled - this was selected during the install and can be changed later but requires a reboot.
- The Firmware level is correct and the latest - this is recommended for new machines.
Configure Network
By now you are probably fed up using the dumb terminal console or VTERM from the HMC and want to get the machine on the network so that you can do the rest of the work from your desk.
While the regular UNIX ifconfig command will you machine up on the network it is not recommended as it is not permanent and will get wiped out at the next reboot.
First, you need to decide which Ethernet port you are going to use for access to the machine for administration and if other ones are going to be used for other purposes like user access or backup. The lsconf command (see above) will detail the Ethernet ports you have or you can use the following:
| Task |
Command |
| List Ethernet ports |
lsdev -Cc adapter |
The names and adapter descriptions might give you clues to where the adapters or ports are in the machine. POWER5 machines have stickers that show you the names of the adapters slots and ports which should match up. The hardware machines for your particular machine might be necessary to fully work it out.
If you can't work it out there is "sledge hammer" solution:
- put an Ethernet cable from your hub/switch into every Ethernet port then configure the first Ethernet and run ping - one of the Ethernet port will then flash and you know which one is which - make a note of it.
To configure the first Ethernet port network it is strongly recommended:
| Task |
Command |
| List Ethernet ports |
smitty tcpip |
You get to this panel manually with smitty --> Communications Applications and Services --> TCP/IP --> Minimum Configuration & Startup.
This lets you setup all the details in one place and one time and it is remembered across reboots.
Select the Ethernet port you want and add the regular network settings including gateway and DNS.
Note select the "en" version (like en0) and not the ent version of the interface (for 99% of all Networks).
But note DO NOT USE THIS FOR THE 2ND OR SUBSEQUENT NETWORKS. Instead use
with smitty --> Communications Applications and Services --> TCP/IP --> Further Configuration pannel
| Task |
Command |
| List Ethernet ports |
smitty configtcp |
Check error message - errrpt and errclear (if/when machine OK)
Check the error logs for errors being reported. Although this sounds obvious, lots of machines try to warn about problems but the system administrators are not listening.
| Task |
Command |
| List errors in brief |
errpt |
| List errors in full |
errpt -a |
- You may need to pipe this in to pg or more ifit is a long list.
If you have had problems during the installation (like having to re-seat adapters or reconnect cables) or have added hardware then you may have lots of error reported. If you are now happy the machines has settled and working fine then it is a good idea to empty the error logs so that any new errors are immediately obvious. First, save the error logs (just in case) and then use errclear to clear the logs.
| Task |
Command |
| List errors in full |
errpt -a > /tmp/errors |
| Clear the errors |
errclear 0 |
Which kernel?
AIX 5.2, the 32-bit kernel is installed by default.
AIX 5.3, the 64-bit kernel is installed on 64-bit hardware and the 32-bit kernel is installed on 32-bit hardware by default.
What are you running now?
| Task |
Command |
| Which kernel version? |
bootinfo -K |
| Which kernel version? |
lsconf |
Which AIX version?
| Task |
Command |
| Which AIX release and Maintenance Level (ML) ? |
oslevel -r |
| Which Maintenance Level (ML) ? |
instfix -i | grep ML |
Paging Space
A classic mistake is not setting up enough paging space. As the old UNIX manuals stated "if you run out of paging space, absolute mayhem is guaranteed". This is not the place for a debate on the size recommended as it depends on the configuration, the applications and workload.
From my experience: I have made the mistake of not adding enough paging space twice during benchmark setup and it is amazing how AIX keeps on running in this extreme condition. If you kill off the benchmark applications, AIX will bounce back OK.
It is worth monitoring paging space in the first few days and weeks.
If you must have a recommendation:
- never go below 2 GB of paging space
- one times memory is good
- RDBMS often have large in memory caches which reduces the need for paging space
- spread out paging spaces across lots of disks to make it high throughput during peaks
- mirror paging space or a single failed disk can take the system down
| Task |
Command |
| List paging spaces |
lsps -s |
| Add paging spaces |
smitty pgsp |
System Environment tuning
There are a number of AIX tunable parameters that are worth checking early on. All these can be found in a single smitty panel.
This includes:
- Maximum number of PROCESSES allowed per user
- Maximum number of pages in block I/O BUFFER CACHE
- Maximum Kbytes of real memory allowed for MBUFS
- Automatically REBOOT system after a crash
- Continuously maintain DISK I/O history
- HIGH water mark for pending write I/Os per file
- LOW water mark for pending write I/Os per file
- Maximum login name length at boot time
- Stack Execution Disable (SED) Mode
- ARG/ENV list size in 4K byte blocks
- CPU Guard
Either take smitty --> System Environments --> Change / Show Characteristics of Operating System
or the following short cut:
| Task |
Command |
| System Environment |
smitty chgsys |
| Add paging spaces |
smitty pgsp |
Open Source and Freely available programs
There are many Open Source programs available pre-compiled for AIX that are very useful. See the "Getting Started" section of this AIX wiki for more details on where to find them. My favorites are below but you will have to make your own mind up:
| Application/Tool |
Comments |
| VNC |
Free X Windows for PC - zero install/setup/graphics/can reconnect, you install and run the VNC Server on AIX |
| vim |
vi with advanced features like colourised code and no AIX maximum line length limits |
| Ethereal |
for network analysis |
| Apache |
you can install the HTTP webserver from IBM which is based on Apache or the original version |
| Samba |
for file access to and from Windows based machines |
| wget |
fetches the contents of a website to you disk |
| MySQL |
the Open Source database |
| GCC compilers |
the GNU Compiler Collection |
| nmon |
for performance monitoring |
If you have a recommendation, why not add it here?
Increase core file system size
The initial installation will create small filesystems to get you started. If you have free disk space is recommended that you increase some of these immediately. For example, many strange things can happen to tools and commands if the /tmp filesystems fills up, including crashes and errors. I recommend that the following filesystems be enlarged to perhaps four times the initial size or more:
| Filesystem |
| /tmp |
| /var |
| /home |
Note: /usr tends to be grown automatically when software is added via installp.
Additional filesystems
Many sites have standard extra filesystems for backup, system admin tools, performance data etc.
These should be added and set up before installing further applications.
Firmware, AIX and software Updates
If this is a stand-alone machine then you should consider updating the system firmware before "going live" in to production to avoid the downtime and disruption.
Every operating system has updates and fixes, and AIX is no different.
See under Maintenance in this AIX Wiki for details of best to update the firmware and AIX and related software.
Install extra packages
The AIX installation will have added the basic AIX system from the media. There are many other optional packages that can be added. It is recommended to review the optional packages and those on the Bonus pack and Expansion Pack.
Extra packages might include:
*Performance related tools
*DOS floppy disk tools (if you have a floppy disk on the machine which is increasingly rare
*Security packages like ssh
*HTTP server which is Apache plus IBM features
Users
Creating users and user groups is best performed by using smitty for small numbers (less than 20). For more than this use smitty to work out the command required by using F6.
Encourage the use of non-root user accounts and not shared accounts for security.
Many applications require a particular user account like oracle for the Oracle database or dbadmin for DB2 database.
If you have more than one RDBMS database, if possible with have different users accounts for each. This will then make Workload manager very simple to use and setup.
Reboot check
Once everything is setup it is worth doing a cold reboot of the system to ensure everything is working correctly. For example, some AIX updates require a reboot anyway. It is often forgotten, leaving you be running on the previous AIX kernel (not a good idea). It also checks that services hardware, such as disks and networks, come online automatically.
Performing this reboot check here avoid any nasty surprises later one when there may be users involved and waiting.
mksysb
The AIX make a system backup command mksysb allows you to snapshot the AIX disks and use them are the basis of a recover or cloning on to an other machine. Having set up the machine exactly the way you like it, now is a good time to save it in case something goes wrong or you need to duplicate the work and want to save lots of time.
Backup and test
Don't forget to set up the backup for the whole system.
At this stage it might not be possible to test the complete recovery - hopefully you will do this after all the applications are set up and the data imported.
It is recommended that you at least perform a backup and follow this by listing out the content of the backup from the media to ensure all the necessary files are present.
Has something important been skipped here?
If yes, why not add it and help others?
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