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OpenSolaris From a Linux Admin and User Perspective
MSa writes "How does OpenSolaris, Sun's effort to free its big-iron OS, fare from a Linux user's point of view? Is it merely a passable curiosity right now, or is it truly worth installing? Linux Format takes OpenSolaris for a test drive, examining the similarities and differences between the OS and a typical Linux distro. If you want to sample the mighty ZFS filesystem, OpenSolaris is definitely the way to go."
Ever since the demise of SGI I haven't looked at anything but Linux / BSD, but this makes me wonder if there is maybe life for Solaris after all.
Would be nice if this was more geared towards the server end of things, which is where I would expect you'd deploy solaris much sooner than on the desktop.
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I'd try Nexenta, except I don't really want to use the Ubuntu repositories for my Linux packages. I'd prefer something with a good KDE desktop.
I'd consider it for a web-server box to test how the kernel handles I/O.
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I love that Sun open sourced it, however I think that the greatest benifit is not that it's open but that the technologies it offers are available to be reproduced on other nix os's. The biggest issue I have with OpenSolaris is that it's still a single vendor OS. If it forks a few times and actually develops a culture and some competition between vendors than I think it will be more appealing.
That's actually what I hate and love about linux. It's a fragmented and ineffecient community, but because it's fragmented I don't have to worry that it's going away any time soon.
Sometimes the best solution is to stop wasting time looking for an easy solution.
Horses for courses, but Solaris has much to offer even for shops that aren't traditionally tied to Sun. Hell, even my private ``1U box in someone else's datacentre'' server for my family is now a Solaris machine.
ian
ZFS kicks ass. Sun really raised the bar with it. There are some other FSs in development (Hammer, btrfs, etc), but they don't have the full integration that ZFS does. Maybe eventually, someone will write a patch so ZFS is just a patch and recompile away in Linux (although that approach is what made minix suck back in the day). Heh, minix will probably have ZFS support before Linux does.
Do you even lift?
These aren't the 'roids you're looking for.
Ahem...
Actually the reverse is true...
Since release 10, Solaris has been pretty well stomping the competition in price, performance and throughput. With Solaris supporting pretty much every type of virtualization (including some not offered anywhere else), it's hard to beat.
Solaris as well as OpenSolaris are free, you can download and use either flavor with no cash outlay. Want support? It's cheaper to buy Solaris support from Sun than to buy Linux support from RedHat.
There's no *tying* with Solaris, it's all about choice. I personally choose Solaris over Linux for pretty much any task.
Who is general failure, and why is he reading my hard drive?
It all depends on the skill-set your admins already have. If you have a shop of 100% Linux admins with no Solaris experience, stay away. If your shop already has some Solaris machines on Sparc, go for it - although you should double check the license.
From my own perspective, I've invested several hours getting it running. Granted, I was running the 200805 OpenSolaris installed on ZFS which had some bugs in the boot process which left my system unbootable a few times. Some follow up releases fixed those problems. But as a guy who's been using Linux since 1993, old habits are hard to break.
This is a boring sig
Stay away?
What if you need real uptime with a load of 80 on a 32 cpu system? Can Linux handle the load and have years of uptime?
Solaris just works and its made for servers. Linux seems always beta quality with its cutting edgness and is desktop oriented. I would not trust my job to it unless its Debian or RHES which costs $$$ as cutting edge features are not needed on a mission critical server. Solaris scales far better than any BSD or Linux distro out there.
Ask any *real* Unix admin who uses both and more than likely they will say Linux is great for small jobs but Solaris is king for anything else.
Oh and the article discussed a scarcity of third party apps. I found the opposite as most server ERP and database apps are on Solaris than Linux.
http://saveie6.com/
However I think this is probably a response to something I've noticed of late, in Asia and South America we don't sell support for Solaris installs any more, they've all moved to Linux, cheaper hardware, a pool of interested young (and therefore cheap) admins, and of course our wonderful software is available on Linux ;)
While Europe and to a lesser extent the US are almost exclusively Solaris (the odd godforsaken HP-UX or AIX box as well to keep me interested) the emerging markets, where the growth is, are moving en-mass to Linux/Open source.
"Linux is for noobs"-The new MS fud strategy
What about hardware support? I keep hearing that the openSolaris kernel just frankly doesn't have many drivers. If I can't install it on my hardware, it isn't doing me any good.
Also, I'd really like to see some basic benchmarks between the kernels. People benchmark the BSD kernel against the Linux kernel on IO, networking, etc.
Show me some quantifiable numbers on openSolaris.
http://blindscribblings.com - Tasty pop-culture in conceptual fashion.
Excerpts from the article:
"... I found OpenSolaris significantly slower than Ubuntu or OpenSUSE..."
"There are fewer packages available than for a mainstream Linux distro, although they do have over a thousand (and certainly enough for a fully-functioning system). The package naming is slightly odd; package names begin with a handful of capital letters (eg SUNW or FSW)."
"ZFS is transactional, meaning that the filesystem is always consistent (so fsck or equivalent isn't used or needed), and snapshots are intentionally both easy and cheap in terms of disk space."
"I'm very impressed with the concepts behind ZFS, but I'm also concerned that cross-functionality with Linux is limited."
"I did find it frustrating to have to relearn commands that I've been using without thinking for years now (eg ifconfig), and right now I'm not convinced that for me it's worth the mental effort, especially given the relative scarcity of external software available."
That's because the Linux folks were worried about the pending USG/CSRG lawsuit so they reimplemented TCP instead of using the BSD TCP stack and utilities like almost everyone else (including Microsoft) did.
Just about any non-Linux UNIX implementation is going to have the BSD TCP.
On the upside the lawsuit did set SCO up the bomb. Oh, it wasn't the only thing by any means (did they actually do ANYTHING right in that lawsuit?), but one of the side effects of the USG/CSRG lawsuit was that a lot of early UNIX code code was open-sourced. Including some of the SCO claimed were examples of "infringing code" in Linux. Come on, folks, wasn't it great to have Dennis Ritchie himself point that out?
I was a Solaris admin back in the early 90s. I preferred SYSV to BSD for a lot of things. But at this point, I'm just not seeing a compelling reason to go back. Sure, ZFS sounds nice, but I don't really want a system that's slower and more RAM-hungry than Linux, and I don't want an OS with a GPL-incompatible license.
GCHQ Quantum Insert installed. If only our tongues were made of glass, how much more careful we would be when we speak
What, no mention of dtrace? Now that's been an excellent part of the Sol10/OpenSol movement IMO.
There are no loopholes. It's either legal or it's not.
If your main concern is whether or not it runs KDE? Then stick with Linux.
Awesome!
dtrace is great, but actually my experience as an administrator is that I use it less than I expect, because the kernel `just works'. I use it to attack badly behaved applications, but I've not used it for tuning anything like as much as I thought I would.
Trying to harden Solaris is a nightmare. Mostly because so many packages in the Solaris install are interdependent. It is either install 90% of the packages or install nothing. Why do they even bother breaking the software packages if this is the end result? Getting rid of RPC can create so many problems it isn't even funny. Both BSD and Linux offer the option of only installing the base package and only choose the services you want with little to no other packages to depend on. This however absolutely cannot be the case for solaris because a single needed software package will require you to install nearly all services.
Where is the "Ignorant" mod tag?
It doesn't matter how many drivers any given kernel supports. All that matters is if it has drivers for the hardware you want to run it on. If you're buying a server then you will typically buy one which comes with support for the OS you want to run and so you won't encounter driver difficulties (although you might pay a bit more).
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Solaris scales far better than any BSD or Linux distro out there.
Yeah, you know, the roadrunner team would like a word with you, as would pretty much everyone in the Top 500. For some business loads Solaris scales better. But the claim the "it scales far better" in general is as absurd as it is patently untrue.
Ask any *real* Unix admin who uses both and more than likely they will say Linux is great for small jobs but Solaris is king for anything else.
Ah, and no true scotsman^W UNIX admin would run a supercomputer, right?
SJW n. One who posts facts.
One of our Linux servers regularly copes with a load in excess of 100. Things slow down, but nothing breaks.
Solaris handles threading a little differently than Linux
It used to be that Solaris used an N:M model while Linux used an N:1 model. Now both use a 1:1 model. There are lots of reasons for this (Matt Dillon gave a really detailed description when explaining why Dragonfly BSD went 1:1 instead of N:M). Basically, it boils down to the fact that debugging threaded C code is such a bitch that people tend not to use high levels of parallelism in C code (which is where N:M really shines). If a language has better support for parallelism then it is easy build an N:M model on top of a 1:1 model (this is what Erlang does, and I believe Java does as well in some versions).
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Stay away?
What if you need real uptime with a load of 80 on a 32 cpu system? Can Linux handle the load and have years of uptime?
Yea, stay away. If you have a load of 80 on a 32 CPU system, you didn't design the hardware or software correctly.
Solaris just works and its made for servers. Linux seems always beta quality with its cutting edgness and is desktop oriented. I would not trust my job to it unless its Debian or RHES which costs $$$ as cutting edge features are not needed on a mission critical server. Solaris scales far better than any BSD or Linux distro out there.
Debian doesn't cost anything, and there's always CentOS if you want the RHEL reliability without the cost.
Ask any *real* Unix admin who uses both and more than likely they will say Linux is great for small jobs but Solaris is king for anything else.
Yea, these were the same Unix admins who used to ask me if I installed the latest kernel patch while they were still using sendmail (and patching it about as frequently). I didn't put a lot of faith in their opinion.
Oh and the article discussed a scarcity of third party apps. I found the opposite as most server ERP and database apps are on Solaris than Linux.
For the big big things, probably. Oracle? Works perfectly fine. I'm building a RAC now using commodity hardware that will probably be 1/3 the price of what it would cost to get something from Sun.
To be fair, I haven't used much Sun equipment (hardware or OS) in the past 6 years or so. There's a number of things they get right, like the Open Firmware. But from an OS and maintenance perspective, does Sun still have patch clusters? Do I have to head over to SunFreeware.com to get useful applications installed? I can provision a Linux server literally in a few minutes, but it would take the better part of a day to get Solaris set up (have to remember to disable telnet, find the latest patch cluster, reboot, install gcc and other apps). Bleah.
Having been a UNIX admin for 23 years and Solaris for 10 years, I'm not sure what you're drinking, but I'm staying away from it.
Solaris support has rocked. We've never had an issue that Sun hasn't been able to solve, and yes, we've thrown them some curves (and sliders for that matter). IBM's support has told us on multiple occasions to re-install the system as a fix for a problem. RedHat we've stumped more often than not. HP? Well - they still can't figure out how to handle more than 8 luns per target for scsi (as well as fibre)...
Solaris performance has been fantastic - outperforming Linux, AIX, HP-UX on modern equipment.
We've migrated workloads to and from Solaris - no big deal - as long as you know what you're doing.
(Our misguided DBA's started migrating from old SunOS 5.8 boxes to Linux - and are now migrating back.)
If you use tools that are available on multiple platforms, migrating isn't all that tough.
If you are developing native language apps, porting isn't terribly difficult although finding workarounds for pesky native quirks is troublesome at times.
So I guess it depends on what you call "experienced"...
Who is general failure, and why is he reading my hard drive?
... between Solaris and Linux in the Enterprise is how they react to abuse - namely stupid people running ton of stupid memory hog applications.
Where I work we have Solaris 9 and 10 boxes running literally unattended for 600+ days - they are shared boxes, meaning lot many different applications run on the same OS/FS/Memory/CPUs .
When a particular app goes haywire and starts (many of them are 64-bit apps) - that particular app just gets a NULL back when there is no longer any memory available. The app can hopefully then calm itself down or release some of its caches etc. but the main point is that the other apps are unaffected and so is the OS.
I would not even begin to think how Linux could handle this. It has this insane notion of handing out virtually any amount of memory to applications whether or not there is actually that much memory and swap available. So when things get out of control the ugly and stupid OOM killer thinks it knows better which app to kill - depending on your luck you could end up with sshd or some other good behaving app being killed to give memory to this bad app.
That is scary. Arguably this is all fixable within the applications but ground reality is that App developers are incompetent - at least where I work, they are.
Plus the newer Solaris releases are close to Linux when it comes to performance. So the only incentive to run Linux is hardware support - if you are on non SPARC hardware that is.
Linux hopefully some day will have a good memory management subsystem soon - less fragmentation, more predictability, good accounting etc. But till that time Solaris for the stupid "Enterprise" .
The OS X version of Virtual box does not support (yet) any of the processor specific virtual machine extensions that speed things up considerably.
I'm not the original poster, but I agree with him wholeheartedly. In my experience, tasks that can be easily parallelized work well in Solaris (web servers, polling servers, etc). However, tasks that are serial in nature (dealing with a stream of events like IDS or syslog) work *horribly* on Solaris.
When we moved some of our log parsing from Solaris/SPARC hardware to similarly priced Debian/x86 hardware, we expected a 3x improvement in performance just due to the CPU...we actually saw a 10x improvement in performance. We attributed this largely to Solaris' aggressive reservation of CPU cycles for other threads...even when we only had one.
What if you need real uptime with a load of 80 on a 32 cpu system? Can Linux handle the load and have years of uptime?
Over 85% of the top 500 super computers in the world run Linux. http://www.top500.org/ as best I can tell almost none run Solaris as most of the Unix is AIX. So all you "Linux's uptime, stability and processing power sucks compared to Unix" old ass fanboys go back to your clubhouse and cry.
Ask any *real* Unix admin who uses both and more than likely they will say Linux is great for small jobs but Solaris is king for anything else.
Wow...if you are a *real* Unix admin it is no wonder Linux came along and is so successful.
"All those moments, will be lost in time...like tears in rain..."
A load of 80 on a 32 cpu system sounds like a poorly architected solution to me. :)
As for the rest, give me a break. One of the benefits Linux is that if you want cutting edgeness and desktop goodies you can have them, but if you're looking for stability and vendor support you can have that too. And it doesn't mean spending a ton of money either - RHEL is relatively cheap and Debian is free (no idea what you're smoking there), as are a number of other options (CentOS, Ubuntu LTS, etc).
We run hundreds of servers on Linux servicing millions of subscribers and have absolutely no stability issues whatsoever. Machines occasionally go down due to hardware faults, power incidents or kernel upgrades, but only a handful of kernel related failures over the years. We've actually had more failures with our Sparc/Solaris machines, generally exhibiting as spontaneous reboots.
Not to mention that an uptime of years generally means someone hasn't been keeping their system patched properly. :)
Couple points:
"ZFS - Are you really using your server for data storage? SAN or NAS should be a better option depending on your price point"
Why not set up a server for data storage? Then you get all the ZFS checksum/auto-heal/snapshot goodness ?
"Zones - I still have yet to see a reason to use this except for dedicated virtualization servers."
Zones are so cheap, I run every single service in a zone so that they can be migrated between machines, any dependencies can be contained, etc. If you haven't seen a use for them it's because you haven't ever used them.
"rcapd - ulimit can do this per process, and there are also multiple 3rd party open source resource limiters."
And yanking the ram stick can do it per-machine. How coarse grained do you want to go before you look like a fool?
In almost every case, the Solaris and other random unix environments could be replaced with Linux at 1/10th the cost."
Solaris is free. Support is 1/3 the price of RHEL. It runs on cheap Dell/Supermicro whiteboxes.
Heavily modified Linux. Ship of Theseus style Linux ( Is it still linux if only the interfaces are the same? )
Unmodified Solaris scales to > 512 CPU's almost linear
Funny you should mention the "desktop orientation" of Linux, considering that any recent Solaris puts on a shiny Gnome suit...
Solaris scales far better than any BSD or Linux distro out there.
Ask any *real* Unix admin who uses both and more than likely they will say Linux is great for small jobs but Solaris is king for anything else.
OK, I'll bite. I've been admin'ing Unix for 12 years, and a user for 20. I've maintained everything from an UltraSparc workstation to E10Ks. Lately (past five years) I've been doing AIX, maintaining over 150 OS instances.
For a test project I've been researching Linux and Solaris for an Oracle RAC installation. I will tell you that, hands down, the Linux network stack is faster. Raw i/o is close, but Linux wins small file writes and reads by a significant margin. BTW, the Sun.com site has a paper comparing Linux filesystems versus UFS, but take it with a grain of salt (look at the machine they use).
Now let's talk about scaling...
Up to the 8 processor machine that I tested (which is a *small* PC system), Linux continues to scale close to linearly for the Oracle/TomCat/Apache workload, as does Solaris. Beyond this I understand things can change, but so be it, that's not the platform I'm needing.
Now certainly you can build a workload requirement that will put Solaris on top, but in the vast majority of installations Linux will do just fine.
Of course there are other factors. RedHat doesn't have the most sterling support (compare it to IBM for example), but I can buy support through IBM (or Oracle or Sun for that matter) if I wanted. This may be the reason for a shop to go with Sun, but I wanted to correct the idea that Linux is not as technically valid as Solaris.
Ok, I'll call you on this one. I'm a SCSA (Solaris Certified System Administrator) and a former Sun SSE. I've worked with Solaris systems going back to 1996 on original Sparcstations (not even Ultrasparcs). I've also worked on Enterprise 10000, 15000, and 25000. We also have a smattering of Sun Fire X4600s, the new AMD Opteron boxes.
I tested Solaris 10 and Red Hat Enterprise Linux 4 (64-bit) on the exact same hardware (X4600), and you know what? Red Hat Enterprise Linux 4 performed better on massive storage I/O than Solaris 10. I have the Oracle ORION benchmarks to prove it. We have over 50 LUNs carved from an HP EVA 8100 and presented to these X4600s, on 4x 4gb HBAs per server. They run Oracle RAC, have 4x quad core AMD Opterons, and Red Hat Enterprise Linux.
Sorry, but Solaris used to be a good OS back in the 90s. They have fallen so far behind it's not even funny. The reality now is that I can run Red Hat and Oracle on a 32 core AMD Opteron box with a hundred LUNs on a fibre channel SAN and it outperforms Solaris now. ZFS is nice, but we use ASM (automated storage management) for Oracle anyway, so ZFS is unnecessary.
Solaris has unfortunately fallen far behind the performance curve, and I doubt they can ever catch up. Your BS about HP not supporting more than 8 LUNs per target is absolutely BS. I can do hundreds of LUNs, and I have systems like that in production.
On support, they all suck. Red Hat, HP, Sun, every one of them sucks. They have all been chasing the bottom and if it ever gets to the point where I'm stumped, they're going to be stumped as well.
"When the president does it, that means it's not illegal." - Richard M. Nixon
Absolute bullshit. I run Red Hat Enterprise Linux (64-bit) on a 4 node AMD Opteron cluster running Oracle RAC. Each server has 32 cores, 128GB of memory, and 8x 4gb HBAs, connected to an HP EVA 8100 SAN. I also tested Solaris 10 on this same hardware, and you know what? It outperforms Solaris 10 on the same hardware. I have the Oracle ORION benchmarks to prove it.
There was a time in the late 90s when Solaris was a far superior OS to Linux for use in the data center. I'm an SCSA, I know, because I started as a Solaris admin long before I worked on Linux. The reality is that now, Linux outperforms Solaris for I/O intensive applications like Oracle database. Why do you think Oracle themselves migrated to Linux a while back? Solaris and Sun have been losing their best and brightest engineers for a long time now, and the quality of their OS shows. It's getting dated. Sure, new features like ZFS are cool, but the core of the OS, where it really counts, hasn't been updated enough to take advantage of the large memory and CPU core footprint that new commodity servers have.
"When the president does it, that means it's not illegal." - Richard M. Nixon
I have had driver problems with Linux as well. Does it have such a site?
PS. You can also check the forums at http://opensolaris.org/os/
""it scales far better" in general is as absurd as it is patently untrue."
How so? With the exception of the SGI implementation, I don't don't of Linux distros out of the box that scale to 100+ processors well (indeed, the usual approach is to run multiple instances of the kernel on each processor or so on large ensembles). When discussing an OS, scalability is usually meant in terms of how the OS itself scales ... not how one's applications can be configured to scale.
So I think the poster's claim that Solaris scales far better is true FOR THE OS itself.
Now, whether THAT matters to your workload (or if your workload scales across many processors via multiple OS instances just fine) is another question entirely.
If 100% is the maximum load, how are you exceeding it? Unless you are using a higher value as the maximum percentage, your math troubles me.
The load average is the number of processes waiting to run, quite different from % CPU usage.
Cause anything which isn't GPL isn't open source, amirite?
"16MB (fuck off, MiB fascists)" - The Mighty Buzzard
OpenSolaris takes quite a bit of time getting used to IMHO coming from FreeBSD, OpenBSD, and many many versions of Linux. I used it because I wanted ZFS, virtulization, and also to try something new.
I did move back to FreeBSD after about a week or so since I thought OpenSolaris brought unnecessary learning curves for someone new. Things like 'ps' being different than every other distro, network interface setup and modification is annoying, the number of programs that you can compile outside of their package manager are slim, and overall not very friendly (I don't want to use the GUI, ever). However, I have 4gb of ram and ZFS really should only be run under 64-bit FreeBSD. Qemu doesn't seem to run, Xen isn't even an option for virtulization and WINE doesn't work under 64-bit (these are the main reasons I bought 4gb of ram in the first place).
ZFS has been running flawlessly on FreeBSD for me thus far, and even the maintainer says he's been using it since her ported it over without a hickup. FreeBSD runs version 6 of ZFS, while OpenSolaris currently runs version 11. It IS true, once you go ZFS you don't go back.
I refuse to run Linux, for personal and limiting reasons, and FreeBSD won't let me virtualize. It seems that in the next few days I'll be biting the bullet and moving back to OpenSolaris. It is very nice that ZFS is seamlessly integrated and snapshots are automatically created when updating the system. This ensures you can easily roll back or boot back into an older install to test different things.
All in all OpenSolaris HAS some potential, but their licensing is very wack and limiting. If Sun wants their OS to evolve and take on more users in the community, the licence will really need to be changed.
One of our Linux servers regularly copes with a load in excess of 100. Things slow down, but nothing breaks.
Be careful with comparisons like these.
Linux lumps disk I/O into the load average, whereas most "other" Unixes don't. I've seen a Linux box with a load of 300+ and idle CPU, and a Sun with a load of 2 that was near unusable because the disks were being thrashed to death.
Comparing the two can be unfair to either side depending on the context. It's apples and laundry detergent.
Brandon Hume
hume -> BOFH.Halifax.NS.Ca, http://WWW.BOFH.Halifax.NS.Ca/
As much as I love tru64, I think it really is time to put this myth to bed. AdvFS is a good solid filesystem and cluster aware too, but it's no ZFS. AdvFS doesn't do any form of RAID other than concatenating disks into disk pools (domains) which can then be populated by filesets (AdvFS speak for filesystems) that share the same domain space. Every enterprise implementation of AdvFS always always has AdvFS sitting on top of some form of hardware or software RAID. AdvFS itself doesn't provide any RAID like data protection or redundancy.
AdvFS doesn't come close to the flexibility and power of ZFS. That's just the plain truth.
Now if you're really interested in Linux's answer to ZFS, you should keep an eye on the development of Btrfs. I wouldn't expect it to be production ready for a couple of years yet, but when it is it should kick ZFS ass!
Only when it forgets where drives are, or wipes configuration during upgrades, or the fact that it's slower than software raid setups in FreeBSD or even Mac OS X.
md on a single box occasionally works. Managing 120 machines with md became a reason to never use md again.
- oZ
// i am here.
No offense taken, but your first line is a typical response from most linux users -- anything that goes wrong is either an admin issue or a hardware issue.
First, md forgetting drives is not a hardware issue. Linux sees the drive, the serial number of the drive is the same, the hardware does not change, the hardware works. Sometimes, you will boot, and it just loses the configuration, so you reconfigure the array, and wait for it to check everything out. For two hours. At 3am.
Wiping out configuration during upgrades happened for two consecutive releases of the master distribution. Everything is backed up, but 3/4's of the machines didn't boot properly after md was upgraded. Turned out this was a pretty known issue. No one ever thought that people would want things migrated. Everyone seems to have a few hours to manually move arrays over.
Look, I'm all for great, open, free technology. The problem is, most people don't think about the big picture. LVM and MD are fine for personal machines that don't do much more than serve up files, or play music, or what have you. Technology like ZFS is designed to be bulletproof, documented, and it has to be supported. Not only that, but given the right amount of RAM, ZFS can outperform many off the shelf RAID systems, and give you flexibility in mirroring, snapshots, and drive support that LVM cannot possibly compare to.
The only reason ZFS hasn't had much news in Linux land is that it 'wasn't invented here' and it isn't GPL. Last I heard, there was a movement underway to reimplement ZFS under the GPL. I would imagine we'll see something in five years or so.
- oZ
// i am here.
Sun has not yet released ZFS an openSolaris under GPLv3, which is the first step.
Next, the Linux kernel would need to be GPLv3.
Linus can relicense all of his contributions to GPLv3, but then the kernel can not include any code currently licensed GPLv2. So actually, every developer who contributed code and maintained copyright on that code would have to be contacted, and all of them would have to agree to relicense the code.
Unlike many other projects where people contributed under "GPLv2 or later", the Linux kernel is basically all "GPLv2 specifically".
It would be a logistic nightmare to relicense the Linux kernel, and many developers have stated they would be opposed to it on principle as well.
Sun could just license ZFS and the openSolaris kernel under GPLv2, but in their eyes it would be effectively giving it away for nothing. The reason they'd consider GPLv3, is to entice the Linux kernel to go the same route, and then both can take from each other.
When Sun discovered that Linux wasn't likely to go GPLv3, they decided not to either.
http://blindscribblings.com - Tasty pop-culture in conceptual fashion.
I gave Solaris 10 more than a fair shake a few months ago (with an eye on its ZFS support) when I had a hard drive fail. I worked pretty hard at getting it to run and really didn't get very far. Note: I've been using Debian for almost 10 years now -- so I'm pretty biased.
.tar.gz package system (excusable for the rare unpackaged Perl module, but unacceptable for the whole damn system). I'm quite admittedly not very knowledgeable about BSD and Unix, but damn those systems seem like a bitch to maintain. And Nexenta simply wasn't there yet.
From what I remember there was an astroturfed Sun-staff-only developer community, little information available online, slow as hell boot time, ZFS boot partition complications, and a broken KDE (the X server didn't work correctly; I have absolutely ZERO problems, even with 3D here in Linux).
And when I looked ahead to maintaining the system (the VAST BULK of where overhead is spent) I didn't see anything that looked as sane or easy as Debian. No incremental updates, just some arcane BSD-esque 'port' or
Solaris 10: pass.