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Data recovery emergency on a downed server... Help please!!
by jvetterli-zC6tqtfhjqE＠public.gmane.org 31 Dec '03

31 Dec '03

> Ilya Palagin wrote: > > For your daily backup operations, a recommend you to use star instead of > > tar. star has a nice "diff" option, which allows to verify backups. Like BTW, GNU tar has a diff option as well (tar df <filename>). JV -- The Toronto Linux Users Group. Meetings: http://tlug.ss.org TLUG requests: Linux topics, No HTML, wrap text below 80 columns How to UNSUBSCRIBE: http://tlug.ss.org/subscribe.shtml

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now off topic: Formatting in C++ (fwd)
by wildberger-iRg7kjdsKiH3fQ9qLvQP4Q＠public.gmane.org 31 Dec '03

31 Dec '03

I find it always amusing when highly intelligent people start arguing about the pros and cons of computer languages. They are all designed to fill a need to accomplish certain tasks. As people have different needs, they will use different tools. The degree of complexity is no measure for comparing one language with another. Languages evolve from simple to more complex to accommodate more and more sophisticred needs. The C++ language bears evidence to this. This makes it more valuable rather than less. For just understanding basic concepts ObjectiveC is a fine language. To all of you, Best Wishes for the New Year. John On December 31, 2003 11:45 am, Tim Writer wrote: > Jing Su <jingsu-26n5VD7DAF2Tm46uYYfjYg at public.gmane.org> writes: > > But computer science curriculums mainly (only?) push the Thread model > > when talking about concurrent execution. I've met many people that have > > a hard time working with asynch event systems, which is too bad. It's > > actually quite clean and simple once you get the gist of it. > > There's a famous quote from Alan Cox which goes something like this: > > Threads are for programmers who don't understand state machines. > Computers are state machines. > > > I wonder what the software landscape would be like if curriculums started > > with ObjectiveC instead of Java, and moved on to concurrent asynch events > > instead of threads. > > I'd like to see them teach two very different languages in parallel in the > first year, e.g. Java and Scheme. I suppose you could argue ObjectiveC is > two very different languages rolled into one. :) -- The Toronto Linux Users Group. Meetings: http://tlug.ss.org TLUG requests: Linux topics, No HTML, wrap text below 80 columns How to UNSUBSCRIBE: http://tlug.ss.org/subscribe.shtml

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now off topic: Formatting in C++ (fwd)
by jingsu-26n5VD7DAF2Tm46uYYfjYg＠public.gmane.org 31 Dec '03

31 Dec '03

> I think if you can grok Java, you can handle Objective C. The object > systems are the same. Further, the same restrictions w.r.t. the types > int and char apply. The only real gotcha is that Objective C's syntax > is a touch bizarre... > > [anObject elementsPerform:aMethod]; > > ie, it looks more like smalltalk. Objective C's syntax is a message passing style. Which made me wonder... many research studies have shown that high-throughput systems run better when designed as asycnronous event systems. Thread-based systems are very hard to push at high-performance ranges. But computer science curriculums mainly (only?) push the Thread model when talking about concurrent execution. I've met many people that have a hard time working with asynch event systems, which is too bad. It's actually quite clean and simple once you get the gist of it. I wonder what the software landscape would be like if curriculums started with ObjectiveC instead of Java, and moved on to concurrent asynch events instead of threads. -- The Toronto Linux Users Group. Meetings: http://tlug.ss.org TLUG requests: Linux topics, No HTML, wrap text below 80 columns How to UNSUBSCRIBE: http://tlug.ss.org/subscribe.shtml

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Formatting in C++ (fwd)
by rgfranks-cmaem7PIVQT44Nm34jS7GywD8/FfD2ys＠public.gmane.org 31 Dec '03

31 Dec '03

>>>>> "Christopher" == Christopher Browne <cbbrowne-HInyCGIudOg at public.gmane.org> writes: Christopher> Objective C is essentially C with an object system Christopher> that uses Smalltalk-like syntax. _Incredibly_ Christopher> simpler than C++'s object system; I would MUCH rather Christopher> write Objective C than C++... I think if you can grok Java, you can handle Objective C. The object systems are the same. Further, the same restrictions w.r.t. the types int and char apply. The only real gotcha is that Objective C's syntax is a touch bizarre... [anObject elementsPerform:aMethod]; ie, it looks more like smalltalk. -- __@ Greg Franks <| _~@ __O _`\<,_ Ottawa, Ontario, Canada |O\ -^\<;^\<, (*)/ (*) (*)--(*)%---/(*) "Where do you want to go today?" Outside. -- The Toronto Linux Users Group. Meetings: http://tlug.ss.org TLUG requests: Linux topics, No HTML, wrap text below 80 columns How to UNSUBSCRIBE: http://tlug.ss.org/subscribe.shtml

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Formatting in C++ (fwd)
by cbbrowne-HInyCGIudOg＠public.gmane.org 30 Dec '03

30 Dec '03

> > > learning a language like Perl, Python, Ruby, Lisp, or Scheme will be a lo t > > > more fun. > > > > Depends on your definition of fun :) > > Many people swear by ObjectiveC, calling it "object oriented C done > right". I know the syntax, but haven't used it enough to be familiar with > it's ups and downs. But if you're looking into learning an object > oriented style language with a C background, ObjC might be the thing to > look into. Objective C is essentially C with an object system that uses Smalltalk-like syntax. _Incredibly_ simpler than C++'s object system; I would MUCH rather write Objective C than C++... It would be expected to be a bit slower than C++ due to more dynamic handling of method dispatch, although that's probably only by a small percentage. -- let name="cbbrowne" and tld="acm.org" in name ^ "@" ^ tld;; http://cbbrowne.com/info/lsf.html Rules of the Evil Overlord #7. "When I've captured my adversary and he says, "Look, before you kill me, will you at least tell me what this is all about?" I'll say, "No." and shoot him. No, on second thought I'll shoot him then say "No."" <http://www.eviloverlord.com/> -- The Toronto Linux Users Group. Meetings: http://tlug.ss.org TLUG requests: Linux topics, No HTML, wrap text below 80 columns How to UNSUBSCRIBE: http://tlug.ss.org/subscribe.shtml

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Formatting in C++ (fwd)
by taavi-LbuTpDkqzNzXI80/IeQp7B2eb7JE58TQ＠public.gmane.org 30 Dec '03

30 Dec '03

On Tue, Dec 30, 2003 at 11:37:32AM -0500, Jing Su wrote: > Many people swear by ObjectiveC, calling it "object oriented C done > right". I know the syntax, but haven't used it enough to be familiar with > it's ups and downs. But if you're looking into learning an object > oriented style language with a C background, ObjC might be the thing to > look into. And before one dismisses ObjC because one has never heard of it, do realise that NeXT was built on it, as is OSX. And yes, GCC 3 compiles ObjC code (generally .m and .h files). This sample chapter from O'Reilly is a good (generic, non Apple- specific despite the book itself) introduction to ObjC: http://www.oreilly.com/catalog/learncocoa2/chapter/index.html -- taa We know today that the brain we are born with is not the finished product it was once thought to be. The structuring of the brain depends very much on experiences gone through in the first hours, days, and weeks of a person's life. --Alice Miller, Ph.D. /*eof*/ -- The Toronto Linux Users Group. Meetings: http://tlug.ss.org TLUG requests: Linux topics, No HTML, wrap text below 80 columns How to UNSUBSCRIBE: http://tlug.ss.org/subscribe.shtml

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Update: Data recovery emergency...
by linux-5ZoueyuiTZhBDgjK7y7TUQ＠public.gmane.org 30 Dec '03

30 Dec '03

First and foremost; THANK YOU to everyone who has helped me out on this!! I decided yesterday to try "Stellar Pheonix Linux" which is a MS-based utility someone here (thank you!) that can attempt data recovery of ext2 and ext3 partitions. It discovered a little over 5,000 files and then Win2k lost the drive entirely. At that, I decided it was time to send it to a data recovery house which I did today. Given the value of the data I decided that I had reached the limit of my (with your help!) expertise. If interested, I will let you know how much (if any) data is saved. Thank you all again! Madison -- The Toronto Linux Users Group. Meetings: http://tlug.ss.org TLUG requests: Linux topics, No HTML, wrap text below 80 columns How to UNSUBSCRIBE: http://tlug.ss.org/subscribe.shtml

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Data recovery emergency on a downed server... Help please!!
by linux-5ZoueyuiTZhBDgjK7y7TUQ＠public.gmane.org 30 Dec '03

30 Dec '03

I have passed the drive off to a data recovery house but if the drive is recovered and the drive is still intact when it's all over I will try this out for personal practice. Thank you!! Madison Robert Brockway wrote: > On Mon, 29 Dec 2003, Madison Kelly wrote: > > Hi Maddy. I hope you got some sleep last night... > > >>I know that backups of the superblock are made, do you know by chance how >>to locate them and/or how to tell the OS to use one for mounting? Also, at > > > No one mentioned this (and I didn't read TLUG yesterday) so here it is: > > /sbin/dumpe2fs /dev/hdxy (where xy is a1, b2, etc) will give you this > info. There is quite a lot of output so redirect it to a file and read it > with less, eg: > > /sbin/dumpe2fs /dev/hde3 > /tmp/hde3.info > > Search for the word "Superblock" > > Now, take that number and use it with e2fsck -b, > > Eg I have "Superblock at 163840" listed for /dev/hde3, so I could try: > > e2fsck -b 163840 /dev/hde3. > > Remember to only work on backup copies! See below. > > >>least two partitions on the drive have gone bad... > > > Different filesystems (partitions) being bad makes it far less likely it > is a filesystem problem. > > Also, the use of dd was mentioned. This is good but there is no need to > write it to a physical drive. You can write the dd to a file and mount it > using loopback and attempt recovery on that. As long as you keep a good > copy of the filesystem file around you can keep trying things over and > over on copies. > > Good luck. > > Rob -- The Toronto Linux Users Group. Meetings: http://tlug.ss.org TLUG requests: Linux topics, No HTML, wrap text below 80 columns How to UNSUBSCRIBE: http://tlug.ss.org/subscribe.shtml

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Data recovery emergency on a downed server... Help please!!
by linux-5ZoueyuiTZhBDgjK7y7TUQ＠public.gmane.org 30 Dec '03

30 Dec '03

Thank you for the info on 'star', I didn't know about that and it definately is a bonus. Thanks! Madison Ilya Palagin wrote: > Madison Kelly wrote: > >> Yep, still under OE (*shudder*) >> >> Thanks for the suggestion, Walter. I did make a copy of the tar.gz >> file but >> I got nothing useful out of it. I am still waiting now for the darn >> activation code for a MS-based ext3-aware data recovery tool... Maybe >> that >> will finally crack my rough luck thus far - if it ever arrives! >> >> Tom, thanks for the note about gunzip -c being the same as zcat. I >> will make >> another backup and give that a go, though my hopes are narrow... Oh, and >> given the current state of my hardware; I certainly would not trust my >> tape >> to make another dump so Walter's suggestion is/was valid. >> >> Madison (who has passed the 24hours mark and wishes she could just get a >> break and then go home!!) > > > For your daily backup operations, a recommend you to use star instead of > tar. star has a nice "diff" option, which allows to verify backups. Like > tar, it's multiplatform, so you can take your tapes to a friend with the > same tape drive and try to restore data on his system to make sure that > your backups make sence. > >> >> ----- Original Message ----- From: "Tom Legrady" <legrady-bJEeYj9oJeDQT0dZR+AlfA at public.gmane.org> >> To: <tlug-lxSQFCZeNF4 at public.gmane.org> >> Sent: Monday, December 29, 2003 6:30 PM >> Subject: Re: [TLUG]: Data recovery emergency on a downed server... Help >> please!! >> >> >> >>> Don't use zcat to decompress a file ... use the appropriate tool, >>> gunzip: >>> >>> gunzip file.tar.gz >>> ls file.tar >>> >>> NB. gunzip -c file.tar.gz is identical to zcat/ >>> >>> >>> He already has a backup of the tar.gz ... it's called a tape >>> >>> Tom >>> >>> Walter Dnes wrote: >>> >>> >>>> On Mon, Dec 29, 2003 at 10:51:45AM -0500, Madison Kelly wrote >>>> >>>> >>>> >>>> >>>>> PS - I got a dd of th last tape that ran (finally) and it is about >>>>> 3.6GB >>>>> (about right). I extracted it as a tar.gz (which should work) but it >> >> >> fails >> >>>>> claiming to not be a gzip archive... Any ideas on that front by >>>>> chance? >>>>> >>>>> >>>> >>>> *MAKE A BACKUP COPY OF THE TAR.GZ FILE FIRST* !!! >>>> >>>> Straight from the man page... >>>> >>>> >>>> >>>>> tar -xvvzf foo.tar.gz >>>>> extract gzipped foo.tar.gz >>>>> >>>>> >>>> >>>> ..did you remember the "z" parameter ? >>>> >>>> I've had similar problems with tar.bz2 archives. I find that doing it >>>> one step at a time works. Note, you will need a *LOT* more diskspace. >>>> >>>> Step 1) zcat filename.tar.gz > filename.tar >>>> The "zcat" executable is named "gzcat" in some versions. Use whichever >>>> one works on your system. >>>> >>>> Step 2) tar -xvf filename.tar -- The Toronto Linux Users Group. Meetings: http://tlug.ss.org TLUG requests: Linux topics, No HTML, wrap text below 80 columns How to UNSUBSCRIBE: http://tlug.ss.org/subscribe.shtml

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Data recovery emergency on a downed server... Help please!!
by linux-5ZoueyuiTZhBDgjK7y7TUQ＠public.gmane.org 30 Dec '03

30 Dec '03

Hi again Byron, Oh, I would say I know a little about RAID... ;) I don't ship a server without -at least- RAID 1 and the new replacement server does indeed have two Seagate Barracuda 7200.7 SATA 120GB drives in software RAID 1 but alas the server that dies was inherited and built on "budget" parts... I am also implementing a tape rotation on a new DDS4 drive where there is a tape for Mon-Thu then four Fri tapes to be rotated. Others have recommended the same scheme like you, and I have personally implemented this scheme for years and it works like a charm... I'll post an update in a sec... Madison Byron Sonne wrote: >> Madison (who has passed the 24hours mark and wishes she could just get a >> break and then go home!!) > > > Please let us know how this all turns out. I'm quite interested in the > ultimate resolution! Sounds like a text book case of the typical failed > drive/bad tape nightmare scenario. > > I've been through this kind of hell but it was when I was part of the > dark side and had to restore MS boxen, or attempt to, from bad > Veritas/BackupExec and/or Legato backups (though most of the time it > worked). Part of the overall procedure (which mind you wasn't followed > regularly for whatever reasons) was periodic restores to make sure > everything would work when called upon. Nothing like having a shelf full > of backups that turn out to be shitworthy in the end. > > Oh; I would avoid CDs for backup... I've used numerous brands across > multiple writers and I'm finding that they are just not trustworthy > enough over time. Some people seem to have something against tape, but > I'd be far more inclined to trust DLT over CD. And keep them drives > clean! It does help. > > My experience with using RAID (level 5 or similar levels of redundancy) > is that it obviates the need for 90% of the restores I would have had to > do in the past. Except, of course, people that want a restore done to > get an old version of a file back. RAID is not a panacea, but who gives > a shit about a busted drive or a 12 hour restore when you can just pop > in a new drive with nary a hiccup? If you got the money, go RAID and > complement it with a good backup system (I like DLT). Given a solid and > well designed IT infrastructure, using good stuff, backups should be > solid, reliable, and never, ever needed. Or for those with massive > amounts of data, go SAN. > > While I'm rambling on, make sure you have clean electrical power, > preferably backed up with a UPS. Numerous restores I've done in the past > would have been avoided if the machine didn't hiccup or crash due to a > brownout or power failure. They don't have to keep your boxen running > for days on end, just enough time to close open files and back down > gracefully. They also help for restores and backups; rather annoying > when a long, long restore craps out midway through due to a power > glitch. Tapes will also be more reliable if your power is clean too, but > I suppose that is conjecture. -- The Toronto Linux Users Group. Meetings: http://tlug.ss.org TLUG requests: Linux topics, No HTML, wrap text below 80 columns How to UNSUBSCRIBE: http://tlug.ss.org/subscribe.shtml

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