Adding/setting up mem, disk, cd drive, sys admin?

[Alan's Home for Wayward Notes File.]

In article <44675 at netnews.upenn.edu>, lau at desci.wharton.upenn.edu (Yan K. Lau) writes:
> We recently got some new hardware for our DECstation 5000/200.  Most of
> the installation seems straight forward but I have a few of questions.
> 
> I added two 8 meg memory boards.  The memory shows up on the hardware
> test.  What do I need to do to make the operating system aware of the
> new memory?  I couldn't find any doc on this, maybe I'm not looking in
> the right place.

	You boot the system.  There's nothing special you need to
	do if the memory is correctly installed.  Now if ULTRIX
	isn't seeing the memory when you boot the system, then
	you have a problem.  Make sure the memory is in contiguous
	slots.  You may also have problems if you're trying to mix
	the older 8 MB boards with the newer 32 MB boards.

	If the addition of the new memory takes you over 64 MB
	then you may want to change the "physmem" parameter in
	the configuration file, rebuild and boot the new kernel.
	The value is used to determine the page tables.  It seems
	that only three values are interesting; less than a low
	water mark, above a high water mark and either side of
	64 MB.  For DECsystems the files of interest are in
	/sys/machine/mips/{genassym.c,vmparam.h}.

> 
> I added 2 RZ57s in an expansion unit to the system.  I ran MAKEDEV and
> newfs.  The results were about 950megs total with 850megs available.  Is
> this normal?  I read somewhere that the system takes about 10% for
> (mumble...mumble).  Is there a way to change this percentage, would one
> want to do this?

	This seems to be normal(*).  The difference between the 850
	and 950 is the 10% reserved free space.  You can change
	this when you create the file system using the -m option
	of newfs(8) or later with the tunefs(8) command.  You may
	not want to though, at least until you need to.  Early
	studies of the Fast File System showed that block allocation
	started becoming slower when the file system was more than
	90% full.  On the other hand, not being able to allocate a
	block knowing that there really is free space, is more than
	a little inconvient.  

	Use the 90% number as a indicator of when you need more disk 
	space.  The disadvantage of having the file system that full 
	is that the performance may suffer.  Blocks allocated to large 
	files will be scattered all over the disk, instead being kept 
	close together.  Small files may also end being scattered all 
	over.  Keep the 10% in reserve and if you really need it later
	you can change it and start looking to get more space or clean 
	up the existing space.

	If you're using the space for archival on-line storage that
	won't change much, then you should be able to set the minfree
	number to whatever is needed.  If you're very careful about
	file placement and allocation the performance might not suffer
	to badly.  I'd guess that you'd want to create the large files
	first and then do the small ones.

	(*) I looked around a bit and the RZ57 seems a bit strange.
	I'll discuss it in a seperate follow-up.

> 
> We got an RRD42 CD drive that has the headphone jack and audio LR outs.
> Does anyone have software that can play music CDs on this drive?  I
> think it's much nicer than the bulky RRD40(?).

	I know that some people internally have written software
	for it.  All of it has been clearly marked "Internal Use
	Only", so it's not available to customers.  I won't be
	surprised to see customer written software showing up
	shortly to do the same thing, if the documentation is
	reasonable.
> 
> Oh, we also got Ultrix 4.2 recently.  I only recently upgraded the systems
> to 4.1. and everything was working so well.

	Read the V4.2 release novel (notes) to see if there is
	any particular feature or bug fix that you need.  Please
	realize that in about six months the CSC will stop treating
	V4.1 as a supported version though.  If you have a support
	contract the first words you hear in answer to a problem
	may be "Please upgrade to V4.mumble".  Beyond that, upgrade
	when it's convient to do so.  Now, if you start exercising
	some mysterious V4.1 bug, then the fix might be upgrade.
	
> 
> Another thing, do you have to run lmf on each machine to install the licenses
> for each product.  We only have a half dozen machines with one acting as the
> server(dms) for the others.  Still, it was a bit tedious typing in all the
> information for each machine to register a product.  There's probably a way
> to type it just once and reuse, no?

	If you have the PAK online you can use this to register it
	from a file:

		# lmf register - < PAK-file

	Once you've typed in all the LMF data and checksum stuff
	you may be able to save a copy of the that to a known file
	before exiting the editor.  If you have DECnet installed
	then you may also be able to use the online PAK as a guide;
	/usr/lib/dnet_shared/{mumble-something-obvious}.
> 
> Sorry if some of these questions seems simple.  We've only recently gotten
> the sys admin doc set and I haven't plowed through all of it yet.

	Please SPR or use the Reader Comments page to let us officially
	know about any problems you have with the documentation.
> 
> Just thought of another thing.  Is there a way to set up yellow pages without
> being a bind server?  Sounds like a wierd question.  What I want to do is
> have a common /etc/passwd, /etc/group files for our DECstations and still use
> our campus-wide name server.

	I have many of the system I manage setup to use bind for
	the hosts and YP for everything else.  Just use svcsetup 
	to pick and choose.
> 
> 
> Yan.
> -- 
>    )~  Yan K. Lau    lau at kings.wharton.upenn.edu      The Wharton School
-- 
Alan Rollow				alan at nabeth.cxn.dec.com