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DRBD To Be Included In Linux Kernel 2.6.33
An anonymous reader writes "The long-time Linux kernel module for block replication over TCP, DRBD, has been accepted as part of the main Linux kernel. Amid much fanfare and some slight controversy, Linus has pulled the DRBD source into the 2.6.33 tree, expected to release February, 2010. DRBD has existed as open source and been available in major distros for 10 years, but lived outside the main kernel tree in the hands of LINBIT, based in Vienna. Being accepted into the main kernel tree means better cooperation and wider user accessibility to HA data replication."
How does this differ from the Network Block Device (NBD)? http://en.wikipedia.org/wiki/Network_block_device
About 15 years ago, I worked for a place that used Tru64. It offered very similar technology to this. Frankly, we found typical hardware solutions to work better. Software is better at some things, but for work like this, you want it done as much in hardware as is possible.
We use DRBD for some very mission critical servers that require total redundancy. Combined with Heartbeat I can fail over from one server to another without any single point of failure. We've been using it for more then 5 years, and never had any major issues with it. It will be great to have it in the mainline kernel.
Why is it so hot? Where am I going? What am I doing in this handbasket?
Just what we need, yet another networking module built into the kernel. Creating a fresh config with the 2.6 series kernels has become even more of a hassle since there are so many modules that are activated by default. To stop the insanity I have to go through and eliminate 90% of what's there so that 'make modules' doesn't take longer than the kernel proper. Most of them are targeted for special applications and don't need to be in a default build.
I am becoming gerund, destroyer of verbs.
so when you get to that part of the kernel config, don't enable it.
It's a good thing the kernel supports modules, so that the 0.1% of users that use this feature can still have it supported without any performance or memory usage detriment to the other 99.9% of users.
It's a kernel module. Don't like it, don't load it.
Your "requirement": "something that the majority of Linux users need, or want" is irrelevant. There are LOTS and LOTS of drivers in the kernel for which this is true, probably MOST of them.
"it's just another layer of complexity" - NOT if you don't install the userland packages or load the kernel module.
"Personally" - you got a lotta nerve representing yourself as having a valid opinion about what does and does not constitute a useful feature.
A closed mouth gathers no foot.
It's not a layer, it's a module. Even if distros compile it, the result is just an extra driver file in the directory. It is only loaded if you need it. How does that add any bloat?
Even at a source code level, it is completely self contained in a directory, other than a couple of one-line changes to tell the build system to compile.
I admin AIX systems for my day job... One thing that's really nice about AIX is that the filesystem and underlying block device is highly integrated. This means that to resize a volume you can run a single command that does it on the fly. For AIX admins who are new to Linux it seems a step backwards and they liken it to HP-UX or some earlier volume management...
Ahh, but the beauty of having separate filesystem and block device is that it's so damn flexible. I can build an LVM volume group on iSCSI LUNs exported from a another system. In that VG I can create a set of LUNs that I can use for the basis of my DRBD volume. In that DRBD volume I can carve out other disks. Or I can multipath them. Or create a software RAID.
Anyhoo, DRBD is a really cool technology. It gives the ability to create HA pairs on the cheap. You can put anything from a shared apache docroot there to the disks for Oracle RAC. With fast networking available for cheap, almost any shop can have the toys that were once only affordable to big companies...
I dont like drbd (though i've used it for a while)... its a massive convoluted and complex mess and fairly inflexible.
Personally, im hoping dm-replicator gets near completion sometime soon though details of it are rather scarce (i do have a kernel built with the dm-replicator patches, but trying to do anything with it seems near impossible)...
I do a fair amount of work inside the storage world and drbd is just such a mess in so many ways.
I sounds very critical and so forth to drbd and thats not the way i mean to come across. What I really am trying to say is that its bloated for the small amount of functionality it does and with a couple of minor tweeks could do much MUCH more. Its a kewl piece of software, but like many FOSS projects has a hideous, weighty config prone to confusion (something you just dont need with DR).
Still, that is the way it is!
There wis a local mid-sized company which recently migrated their workstations from Windows XP to Linux. Firefox, Thunderbird, OpenOffice...it did everything they needed to do, and it was free!
Productivity dropped sharply shortly after the migration. No prob, everybody thought, just a temporary result of the learning curve. Rolling out a standard backup image was a huge hassle because there were different brands and models of workstations.
Updates would break the entire operating system and the IT staff had to hire temps just to fix driver problems and roll the dice editing config files. Users were complaining about having to sit aside all day while their workstations were being "fixed". Users were becoming frustrated with not knowing how to do anything without getting "file permissions" errors, and some of them threatened to quit altogether after a training session showed them how to use the terminal to navigate to a word document and use sudo to open it, while the same action would have been only a double-click on Windows. It took 5 months before the computers were perfectly configured and everybody got the hang of using Linux, but it still didn't solve the problem of random OS lockups which caused a lot of lost data.
Why is Linux still locking up? Windows fixed that problem years ago with 2k/XP!
Uhhh,, "-1 Truth Hurts" ?
Honestly, unless you are tuning your operating system for some very specialized use, bloat isn't an issue.
The vast majority of users don't need to worry about bloat, and you'd have to seriously try to screw up Linux to make it as bloated as, say, Windows 7.
I am looking right now that the C:\WINDOWS directory for a windows 7 machine and its sitting at 11GB in size.
who prays for Satan? Who in 18 centuries has had the humanity to pray for the 1 sinner that needed it most? ~Mark Twain
Yes but what does it all mean?
Don't be apathetic. Procrastinate!
Lot of different ways to get similar results. You might say I'm cloudy on which of these is really equivalent, is a good idea or the best way to do it, or has good performance.
There is Gluster which sits on top of any existing disk file system, via FUSE, I think. No kernel module needed, only runs a daemon. I tried version 2, and it worked fine, however I didn't demand much of it. They've just come out with version 3.0 that doesn't need libfuse anymore.
Or there's Lustre, which does need a kernel module, and has its own file system.
Are some of the new file systems under development, such as btrfs, going to have distributed, networked operation as a basic feature? I recall hearing that ZFS has some ability along those lines.
Or we don't bother with distribution at the file system level because we're using some sort of cloud where as part of distributing everything, the file systems are distributed too.
I haven't heard of NBD before. Of course there's NFS, which seemingly everyone agrees is slow and obsolete.
Intellectual Property is a monopolistic, selfish, and defective concept. It is "tyranny over the mind of man"
FreeBSD users have been doing it for 7 years with the default kernel. I guess that's one reason why it's more popular with companies that depend on HA, such as Bank of America. I love having ZFS as well, the combination is sooooo bad ass :-)
For those that run BRDB and want to try it, can read this.
I for one welcome our obediant mod overlords. Mod this 'underrated', robots!
that looks more like some copy-paste troll.
"use the terminal to navigate to a word document and use sudo to open it" ? rrrrrrrrrrrrright.
Rich
I've been using linux as my main OS for the past 6 to 7 years and in all this time I never experienced any linux lockup., not even back in the beginning where we couldn't do away with compiling software by hand (where the "you need to know how to program to use linux!" was born) and when the only way to make my DSL modem work was to run a weird, convoluted shell script through the command line. So, that "lockup" accusation is, at least, very odd, particularly in this day and age.
Moreover, that weird accusation of "file permissions errors" and the need to have IT staff hired with the sole purpose of "fixing drivers" and "edit config files" also sounds like bullshit to me, specially in today's world and even after the GP stated that their workstations worked with XP and win2k, a pair of OSes which are more problematic, less stable and with a less extensive hardware support than today's popular linux distributions.
And of course, let's not forget that the GP made a point in launching that long-winded anti-linux troll while intentionally keeping out fundamental details such as what linux distribution was supposed to be installed, not to mention that it was posted anonymously. To put it in other words, the GP wrote that post intending to attack the entire linux world, insinuating that that sort of problem affects each and all distros and not a specific one, and it did it so intending to be a troll.
So, it would only be seen as "-1 truth hurts" if you didn't read the post and you also considered a "your mother is a whore" type of post as "-1 truth hurts". It's not, it is meant to insult and it is perfectly void of any objective statement.
Slashdot, fix your code or at least hire someone who is competent at it to do it for you.
This isn't really something that the majority of Linux users need, or want compiled into their kernel.
So it's great that they don't need, nor they are forced to, have this kernel module in their kernel. And it is also great that, as everyone (including you) has access to the source code, it is possible to cherry pick what feature to have in the OS kernel. Isn't linux awesome?
For them, it's just another layer of complexity - something which linux zealots routinely lambast Microsoft for.
Source, please? Or are you mindlessly throwing baseless accusations?
It'll be interesting to see how many distros include it in their kernel compiles by default.
My guess is not many. But you know what? As it's a kernel module, if a distro doesn't include it then you can include it and if a distro does include it then you can also remove it. Isn't linux awesome?
Personally if you need this kind of installation, you better be sharper enough to recompile the support into the kernel.
And thankfully that's what linux gives you. More so, even if you don't need it you can also remove it. It's an odd bloat to have, being able to not only remove hand-picked features right out of the OS kernel and but also add them if you see fit. Isn't linux awesome?
Slashdot, fix your code or at least hire someone who is competent at it to do it for you.
It isn't. In our mid/large company, we have hundreds of Linux workstations, and they've all been working for years without a single hitch, from day one. No permission problems, never had an update causing significant issues, don't even ALLOW users to get a command-line, etc. Vastly easier to debug when there is a problem, and has allowed the company to replace a large group of Windows experts with a small group of Linux experts, and the vastly improved productivity has allowed the company to significantly reduce the number of employees (or rather, just cease to replace them when there is turnover).
Just the other day I noticed the uptime on one of the Linux workstations was over a year at this point. No lockups. The few issues we've had with the systems have been directly traced to hardware problems.
If yours is a true story (which I seriously doubt) you should look at hiring at least one half-way decent Linux SysAdmin at a reasonable salary to fix the pathological issues with the installation which was likely done by minimum-wage idiots without a clue.
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
Ah, Linux gets disk level clustering?
It is interesting to compare with what VMS offered 25 years ago:
- VMS could have multiple nodes (can DRBD? It is not obvious from the web site.)
- All VMS nodes have read and write access to the file systems
- The distributed lock manager helps with file locking in this case.
- VMS has the concept of quorum to avoid the "split brain" syndrom mentioned on the web page.
)9TSS
Half of that is probably due to the winsxs folder which has the same files with different names (so it really isn't using as much space as it appears).
See:
http://www.winvistaclub.com/f16.html
Then another 2+GB is the installer files.
For them, it's just another layer of complexity - something which linux zealots routinely lambast Microsoft for.
Source, please? Or are you mindlessly throwing baseless accusations?
Just cruise Slashdot for examples of people picking on MS for included features and support that few folks need. Particularly when they turn into vulnerabilities (doesn't help when those features are enabled by default). I blame MS for that, as I get to go disable all those features like remote dcom and posix support when I harden boxes. Or I simply use something like nlite to trim all the fluff away. Microsoft is getting better, mostly on the server side, of disabling or not installing all the features unless actually needed.
I think people think linux is "unreliable" because they don't attribute lockups to their binary video card drivers. I've been using Linux as my main OS at home since late 1992, and have run my home PC 24x7 since 2000, and can only remember one kernel panic in all that time - but then again, I've never run a binary kernel module. If you think it is normal to run 3rd party drivers, because you're used to that from the Windows word, and then you do so under Linux, and Linux fails, you're unlikely to attribute the failure to the binary module and the risks of running one, but to Linux itself.
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