Regarding RAIDs and hotswaps - I prefer to do a full backup, then put said backup offline, then insert the new hard drive for a rebuild session.
Never had the need to restore from backups.
1896 posts • joined 6 Jan 2010
Now that VLB got mentioned, anybody who managed to get rock solid performance from that piece of duff?
I managed to scrounge a PC together from parts and! VLB!!! video!
Suffice to say I tossed said VLB video card and installed a PCI video card - was much more reliabler (and faster).
In another instance, Novell Netware and an VLB IDE card = disaster, had to reinstall that thing twice before tossing said VLB card and installing a normal IDE card - never had any issue from that any more. And yes, the VLB NLM was loaded.
Bah. I used OS/2 (from 2.1 up to 4) - the DOS session had most of the 640k available.
No more struggling to get preciouses RAM to be freed...
But I still remember the fun to be had by trying to optimize a Novell Netware 3.1 boot image for maximum RAM, and have IPX/SPX loaded... Netware 4 changed the rules of the game by foisting an entirely diffferent method upon us, and we had to redo the boot images until we got a working one with enough RAM for the DOS apps to run....
Oki dot matrix printers had a channel to guide the printerer head IIRC. Sometime this channel would get clogged wiith debris (paper from the paper feeder perforated strips on both sides of the paper) causing misprints and other funny stuff.
Was relatively easy to clean with a paper clip, but best results was that you strip the printer completely.
And frequently a wee drappie of oil wil manage to speed things up, especially if applied in minuscule amounts to the polished bar carrying the printerer head (forgot what it is called).
Glad to see gibbermints are the same no matter where you may reside/live/have rumpypumpy.
Seems all they do is waste taxpayer money and is planning extra taxes etc so as to maximize oinkage.
Lord Dimwit Flathead the Excessive surely had something going with his plans for a 100% tax rate...
Time for a Linux distro with a WINE environment (and Winbox etc preinstalled) which you can boot from a CD then?
Meaning you will have to make a plan with exporting the Mikrotik configuration to a separate and well-marked memory stick/flash disk/external hard drive/whatever just to have a backup of your running configs.
I'll leave this here for all of you to ruminate on...
(the original can be found at https://web.archive.org/web/20090208023917/http://justpasha.org/folk/rm.html thanks to the Wayback Machine).
Have you ever left your terminal logged in, only to find when you came back to it that a (supposed) friend had typed rm -rf ~/* and was hovering over the keyboard with threats along the lines of "lend me a fiver 'til Thursday, or I hit return"? Undoubtedly the person in question would not have had the nerve to inflict such a trauma upon you, and was doing it in jest. So you've probably never experienced the worst of such disasters...
It was a quiet Wednesday afternoon. Wednesday, 1st October, 15:15 BST, to be precise, when Peter, an office-mate of mine, leaned away from his terminal and said to me, "Mario, I'm having a little trouble sending mail." Knowing that msg was capable of confusing even the most capable of people, I sauntered over to his terminal to see what was wrong. A strange error message of the form (I forget the exact details) "cannot access /foo/bar for userid 147" had been issued by msg. My first thought was "Who's userid 147?; the sender of the message, the destination, or what?" So I leant over to another terminal, already logged in, and typed grep 147 /etc/passwd only to receive the response /etc/passwd: No such file or directory. Instantly, I guessed that something was amiss. This was confirmed when in response to ls /etc I got ls: not found.
I suggested to Peter that it would be a good idea not to try anything for a while, and went off to find our system manager.
When I arrived at his office, his door was ajar, and within ten seconds I realised what the problem was. James, our manager, was sat down, head in hands, hands between knees, as one whose world has just come to an end. Our newly-appointed system programmer, Neil, was beside him, gazing listlessly at the screen of his terminal. And at the top of the screen I spied the following lines:
# rm -rf *
Oh, shit, I thought. That would just about explain it.
I can't remember what happened in the succeeding minutes; my memory is just a blur. I do remember trying ls (again), ps, who and maybe a few other commands beside, all to no avail. The next thing I remember was being at my terminal again (a multi-window graphics terminal), and typing
I owe a debt of thanks to David Korn for making echo a built-in of his shell; needless to say, /bin, together with /bin/echo, had been deleted. What transpired in the next few minutes was that /dev, /etc and /lib had also gone in their entirety; fortunately Neil had interrupted rm while it was somewhere down below /news, and /tmp, /usr and /users were all untouched.
Meanwhile James had made for our tape cupboard and had retrieved what claimed to be a dump tape of the root filesystem, taken four weeks earlier. The pressing question was, "How do we recover the contents of the tape?". Not only had we lost /etc/restore, but all of the device entries for the tape deck had vanished. And where does mknod live? You guessed it, /etc. How about recovery across Ethernet of any of this from another VAX? Well, /bin/tar had gone, and thoughtfully the Berkeley people had put rcp in /bin in the 4.3 distribution. What's more, none of the Ether stuff wanted to know without /etc/hosts at least. We found a version of cpio in /usr/local, but that was unlikely to do us any good without a tape deck.
Alternatively, we could get the boot tape out and rebuild the root filesystem, but neither James nor Neil had done that before, and we weren't sure that the first thing to happen would be that the whole disk would be re-formatted, losing all our user files. (We take dumps of the user files every Thursday; by Murphy's Law this had to happen on a Wednesday). Another solution might be to borrow a disk from another VAX, boot off that, and tidy up later, but that would have entailed calling the DEC engineer out, at the very least. We had a number of users in the final throes of writing up PhD theses and the loss of a maybe a weeks' work (not to mention the machine down time) was unthinkable.
So, what to do? The next idea was to write a program to make a device descriptor for the tape deck, but we all know where cc, as and ld live. Or maybe make skeletal entries for /etc/passwd, /etc/hosts and so on, so that /usr/bin/ftp would work. By sheer luck, I had a gnu emacs still running in one of my windows, which we could use to create passwd, etc., but the first step was to create a directory to put them in. Of course /bin/mkdir had gone, and so had /bin/mv, so we couldn't rename /tmp to /etc. However, this looked like a reasonable line of attack.
By now we had been joined by Alasdair, our resident UNIX guru, and as luck would have it, someone who knows VAX assembler. So our plan became this: write a program in assembler which would either rename /tmp to /etc, or make /etc, assemble it on another VAX, uuencode it, type in the uuencoded file using my gnu, uudecode it (some bright spark had thought to put uudecode in /usr/bin), run it, and hey presto, it would all be plain sailing from there. By yet another miracle of good fortune, the terminal from which the damage had been done was still su'd to root (su is in /bin, remember?), so at least we stood a chance of all this working.
Off we set on our merry way, and within only an hour we had managed to concoct the dozen or so lines of assembler to create /etc. The stripped binary was only 76 bytes long, so we converted it to hex (slightly more readable than the output of uuencode), and typed it in using my editor. If any of you ever have the same problem, here's the hex for future reference:
070100002c000000000000000000000000000000000000000000000000000000 0000dd8fff010000dd8f27000000fb02ef07000000fb01ef070000000000bc8f 8800040000bc012f65746300
I had a handy program around (doesn't everybody?) for converting ASCII hex to binary, and the output of /usr/bin/sum tallied with our original binary. But hang on - how do you set execute permission without /bin/chmod? A few seconds thought (which as usual, lasted a couple of minutes) suggested that we write the binary on top of an already existing binary, owned by me... problem solved.
So along we trotted to the terminal with the root login, carefully remembered to set the umask to 0 (so that I could create files in it using my gnu), and ran the binary. So now we had a /etc, writable by all. From there it was but a few easy steps to creating passwd, hosts, services, protocols, (etc), and then ftp was willing to play ball. Then we recovered the contents of /bin across the ether (it's amazing how much you come to miss ls after just a few, short hours), and selected files from /etc. The key file was /etc/rrestore, with which we recovered /dev from the dump tape, and the rest is history.
Now, you're asking yourself (as I am), what's the moral of this story? Well, for one thing, you must always remember the immortal words, DON'T PANIC. Our initial reaction was to reboot the machine and try everything as single user, but it's unlikely it would have come up without /etc/init and /bin/sh. Rational thought saved us from this one.
The next thing to remember is that UNIX tools really can be put to unusual purposes. Even without my gnuemacs, we could have survived by using, say, /usr/bin/grep as a substitute for /bin/cat.
And the final thing is, it's amazing how much of the system you can delete without it falling apart completely. Apart from the fact that nobody could login (/bin/login?), and most of the useful commands had gone, everything else seemed normal. Of course, some things can't stand life without say /etc/termcap, or /dev/kmem, or /etc/utmp, but by and large it all hangs together.
I shall leave you with this question: if you were placed in the same situation, and had the presence of mind that always comes with hindsight, could you have got out of it in a simpler or easier way?
"An issue not mentioned in the research note is the rising cost of features people don't want."
"Manufacturers are spending more and more for less and less gain."
1, Bring back the earphone jack.
2. Retina displays - are these really neccessary?
3. Just glom a good camera onto it, we really don't need fancy poofty gimmickry stuff such as slo-mo, or dual camera whatnots. Heck, I use my camera so seldom.
4. Bigger is not always better. Except for the battery.
5. Thin phones are so overrated like a wet, stinky fart.
6. Try to glom less bloatware on the phone itself.
7. Allow the customer to customize the phone the way he/she/it wants. Not what you want the customer to have, what the customer wants. End of story.
Based on that, I think that *every* company will need to have an inhouse IT department to stop their IP from leaking out. Well, those that's large enough to be able to afford one, that is. *cough*
One of the pitfalls of outsourcing - quite an easy way of obtaining some other company's IP by spear phishing somebody and causing issues with that PC - and they then send it out for repairs, and you can access it at leisure via a bribed techie.
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