[H-GEN] Simple Linux editors

[Greg Black]

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Robert Kearey wrote:

| > It's the ability to function usefully in such circumstances that
| > makes the best people stand out from the crowd.
| 
| What - to dive into an unknown system, with unknown problems, and start 
| blundering around with a basic text editor?
| 
| *shudder*
| 
| Gods, if I ever saw a consultant doing that, I'd be *demanding*, in no 
| uncertain terms, to know what the hell he or she is doing.
| 
| I'm sure that's not quite what you mean, though.

No, it's not even close to what I meant.  I was talking about a
case where some organisation has been doing whatever they do for
many years and have discovered one dark night that they have
shot themselves in the foot.  At this point, fearing a total
disaster, they call for outside help.  When the help arrives,
they explain as far as they can what's wrong and state their
expectations and they invite the help to do whatever s/he can to
solve the problem.

Sometimes, in such a scenario, editing of system files is
necessary and sometimes the only editor available is ed.  In
those cases, ability to use ed is a useful skill.

This does not involve anything that resembles diving into
unknown problems and blundering around.

In one case I can recall with some of the clarity that comes
from a late night call to a completely unknown system, one of
the many indicators that the system had been in rather unskilled
hands was the existence of several thousand oddly-named files in
several thousand oddly-named directories: the directories were
all named as in the C string "\b\b\b\b\b\b\b\b\b\b\b\b\b\b"
(i.e., 14 backspace characters) and the files were all named
"*.c".  And no, the system had not been hacked.

Obviously, ed did not play a part in solving that particular
problem, but it was most useful in solving the problem they
called me in to solve.

| if all you've 
| got left is ed then something is /extremely wrong/ and it's time to 
| rethink your strategy.

I've never suggested that you should do nothing until disaster
strikes and then expect ed to save the world.  I've simply been
talking about the use of a tool for editing files that will
almost certainly be available in the darkest moment if it so
happens that you are asked to come to the rescue.

| Greg, cut it out with the snippy intellectual hairshirtness, please.

Sorry, I didn't mean to be offensive.  I did write some of that
stuff at the end of a very long day that was notable for the
number of people who were angry with me because of problems they
had caused.  Perhaps some of my mood leaked into this exchange.

| All 
| problems that need to be solved, quicksmart, are Real Problems [tm].

I agree completely.

| What, it'll reconfigure your buggy router? It'll save you from a 
| corrupted kernel image, or intermittently dodgy RAM? Or any of the 
| umpty-thousand non-trivial foobars that can occur with a modern complex 
| server?

I don't think I claimed any of these things for ed.  Please
stick to the facts here.  I've said that ed is an editor, and
that it's useful in that role.

| Not many people are placed in situations where they need to bootstrap a 
| minimal unix off a tape via a dot-matrix teletype these days. That's 
| just how it is.

True, but not really relevant.  I have not said that everybody
must learn to be proficient with ed.  Sometimes, and in some
quite surprising situations, being able to deal with disasters
that should not have happened is useful -- perhaps you recall
the recent thread about recovering data from a dead disk that
clearly should have been backed up?

| > In many situations that I've been involved with, the entire
| > hardware is one of a kind custom stuff that would take months to
| > replace[1].  You don't just build a new one and roll it out.
| > And there are many more modes of "failure" than you're taking
| > into account.
| 
| A point, but that'd suggest (to my perhaps naive and inexperienced mind) 
| that they haven't taken hardware redundancy seriously. Not your problem, 
| I guess, when the crap goes down, so long as you're commanding the big 
| dollars for you skills.

In one such case, they had taken redundancy reasonably seriously
but the other hardware items were all in aircraft that needed to
keep flying and could not just have their systems ripped out so
the people on the ground could have a spare.  This was poor
planning and one thing I did while helping them out was to get
a group of hardware people together to start cloning some of the
obsolete components that would be needed to build a backup
system.

| > [1] No, this isn't a wise choice, but defence budgets are so
| >     structured that unwise choices tend to get made rather
| >     frequently.  And we have to work with what we've got.
| 
| Eep.

My words exactly :-)

| I rather think that you and I work in very different worlds, Greg.

I don't know your work world, but I have been describing real
events from mine.

| Whilst I don't agree with your position that not knowing inscrutable ed 
| off by heart is an offense unto good order and makes one a Bad and 
| Incompetent Sysadmin, I do see the value of having such skills. I'll 
| certainly brush up on them myself.

Well, I consider that a good outcome from this.  And, to be
clear about this, I don't despise people who can't drive ed
without the man page in front of them -- but I do think knowing
ed is a useful skill for sys admins and programmers.  I don't
ever recommend it for other people.

Greg

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