NIM Basics

Principle : -

We use NIM or any such network installation managers for ease of administration. Does that not help ? , to install a new software or to re-install operating system, we [ the sysads ] need not run all the way to the datacentre and locate the machine. Then it's CD drive and then replace the CDs etc. So that was the reason why such products came in. It also helps you to do the work more efficient and in a controlled and managed manner.

I am not sure what product solaris uses , but HPUX uses something called IGNITE-UX which does almost the same thing. So most of the enterprise operating systems have this option ot having a NIM kind product.

In principle they make use of tftp, bootp and NFS utilities to do the job. For example, an AIX installation i would guess goes as follows ,

a) Boot from the CD
b) Now this guy is an operating system itself, creates a memfs and installs a basic operating system and then runs the actual OS installation program under the temporary operating system created on the system memory.

So a network installation manager product does the same thing but in a diffrent way.

a) Configure NIM server as a bootp server and is ready to deploy a basic boot file to get the installation started.
b) It transfers a little program(s) via tftp onto the client and then runs that program.
c) Most of the products uses NFS mount to get the media [ We already configured the required resources on the NIM server ]

d) Run the installation program.

I may not be fully correct but that is what I understood having worked on IGNITE and NIM. There may be small vendor specific changes but basically they are the same.

NIM :-

NIM is a client server product. We can define resources on the NIM server and bundle them to get the things done.

The scope of NIM is much more than what I am planning to cover in this note.

I would set up the following on a NIM Server [ A basic one ]

a) NIM Master
b) NIM Clients
c) Spot, mksysb, lpp source and image.data [ one each for each operating system in the nim clients ]

You can do all this by /usr/lpp/bos.sysmgt/nim/methods/nim_master_setup or then smitty eznim.

You can create a spot, mksysb and lpp source for another operating system version by mounting the first CD on the nim and then creating one.

So there you go, you are ready for a NIM operation.

Check the man pages for nim command and you can do almost all the operations from there.

For example, nim -o allocate -a spot=aix52spot -a lpp_source=aix52lppsrc -a mksysb=aix52basicmksysb machine1

Allocated spot resource aix53 spot , lpp_source resource aix52lppsrc and mksysb resource aix52basicmksysb for machine1. All you got to do after this is to boot the client to the SMS , configure network interfaces and then boot through the network.

Phew .... That is all about NIM what I wanted to know as a newbie, the product is not just what I have mentioned , I would leave it to you to do the further R&D.