Quote:
Originally posted by linux_eval
We would like to learn about your success stories in more details. Hopefully, that will help us in our decision-making process as to what to look out for.
We are currently evaluating Redhat and Novell - please help us with your suggestions or advice.
If it's easier for you to chat over phone, please email us your contact info and best time to call. Thanks.
Fred
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Disclaimer - everything I am about to say is my opinion, and has nothing to do with my employer or current contract. I can't really discuss my current Linux work in too much detail, but it is an enterprise rollout.
Now that the obligatory stuff is out the way, here we go
I've used Linux successfully in a range of organisations from 2 people to just over 4000. I've used them for everything from File / Printer / SoHo networking solutions to application servers for enterprise applications.
When I was working in web hosting, we eventually moved away from Linux and to FreeBSD. This was largely because there were some MONSTER problems with Linux at the time (circa kernel 2.2.19 with the VM nightmares and the problems with the Intel Etherexpress cards). FreeBSD in a web environment made a lot more sense for us because of the upgradability of the boxes. I've still got servers out there that I deployed at FreeBSD 4.3 and they're now running 4.10. They've never been out of the colo for upgrades, etc. We upgrade in place with no disruption to our clients other than the two reboots required. Linux can do this, but generally the RPM based distributions suffer - if you want this kind of in-place upgradability, look to Debian or Gentoo. Also, our reason for moving to FreeBSD is less relevant now that 2.4 is stable and healthy.
Back to Linux
The biggest thing to decide is what you want out of the system. If you're looking to replace enterprise applications in a large corp, you'll often strugle to get something like Gentoo or Debian in the door - these people still need the security of a vendor to phone and yell at, so you're best looking at Red Hat or Novell. Having said this, you are just paying for comfort - Red Hat's support is, not to put too fine a point on it, crap! I've had such gems back from them as "We do not advise that you hot-swap hard disks while the server is powered on as this may cause damage to your hardware. You should power your server down before replacing disks.". This was despite the ticket being raised with the information that the server is a Sun that is designed to have disks hot swapped! You'll also struggle to get them to support a system if you've customised your kernel or are running a filesystem that they don't support (And they only support ext2 and ext3, not xfs, not jfs and not reiser, although I believe they plan to add support for some of these later).
I've not been able to test Novell's support because they couldn't offer us a trial agreement with an NDA and support for a 3 month period. This is a pity because SLES9 (SuSE Linux Enterprise Server) is far superior to RHEL AS 3 from an installation and maintenance perspective. The SuSE tools all work well, have good, context based help, and work in both text and graphical mode. Many of the Red Hat configuration tools only work in graphical mode, have poor or no help, and are prone to crashing when you do something wrong instead of giving you an error message. I've spent a lot of time reading Python tracebacks lately.
If you're looking for a small number of servers, SLES wins hands down. It is a technically superior product IMHO. However, many of the ISVs don't have their apps ready for SLES9 yet because it only went GA recently. This may hurt them during current selection processes.
If you're looking to manage a large number of servers, Red Hat have the RHN and the Satellite product. It's not cheap, but it is very cool, despite the fact that you'll often find yourself staring at Python tracebacks... You'd think that the money you drop on this (and for a small company, it's prohibitive!), you'd get an error, but maybe that will change as things mature. It's also quite easy to sell to managers, especially if they are familiar with Microsoft SMS for managing software on workstations and servers. The functionality that Satellite provides could _mostly_ be replaced by a combination of a PXEBoot solution using TFTP and DHCP, kickstart (which you get out of the box), cfengine for managing configuration files and Yum for updates. You loose the centralised single solution, and you can't present quite the same shine to management, but you'd get about 75% of the functionality. I'm not aware of a central management solution from Novell, which is one of the main drivers behind my use of Red Hat in large corps. This is unfortunate because this is the only thing driving the choice right now
If you're going for a vendor supported Linux solution, your TCO isn't going to look much cheaper than Sun. From figures I've recently been looking at, it appears that Fujitsu's Prime Power solution with Solaris may actually have a lower TCO than vendor supported Linux. Corps like to go with vendor support because it takes the burden of actually having to have their own in-house specialists away. In all honesty though, to make a success of Linux, you either need in-house specialists to support your support and development teams, or you need an entirely outsourced server solution. The vendor is great for problems that don't need immediate solutions, but normally Experts Exchange or Google beats Red Hat support on working resolutions in all my testing so far.
So your TCO is up the creek, why go Linux ? Well, the main reason we're seeing is performance. The price - performance blows sun out of the water! A report in a proprietry application that took between 4 and 6 hours on a Sun takes 30 minutes on an Intel box that costs roughly half of what the Sun did. That means an entire team can suddenly get REAL value out of an application instead of just queueing up reports to run overnight!
That's the good news - what about the bad ? Well, Linux still scares people up the foodchain. Most people understand where the OS came from, but many people still doubt that it can sustain it's current growth. They're worried about scalability, which sounds odd, but when you find out that they're used to running machines with 32GB ram and upwards of 16 processors, you start to see why. Comments from core developers that they will leave stability to the vendors and focus on features / innovation in a supposedly stable kernel branch don't help. A lot of companies are looking to Linux as a way to break current vendor locks. A lot of big shops are Sun / Veritas / Oracle shackled. Now that Oracle is supported on Linux and we have most of what we need from VxVM in LVM and md, it is a good way to throw off those shackles. But when a director hears that stability is up to the vendor, he sees lock-in 5 years down the road. And who can blame him really ? He doesn't have the technical knowledge to place this in context, and he's got to sell this to the board. It's normally his head on the block when things go pear-shaped.
Another issue is fragmentation. Say what you like about this, but fragmentation is a reality, and it is starting to put developers off. Having to maintain separate packages for SuSE and Red Hat is an expense that they could live without. Certifying your product on Red Hat AS 3 only to have it fail during the lifetime of AS 3 because the threading model in the Kernel changes is a cost that they didn't factor into their development / support of that release of the product, and it's another thing that they could live without. If the Linux movement can't keep stability in major kernel releases (and I don't mean 200+ days uptime, I mean consistent API / ABI once the kernel version is blessed as being stable) then I believe that we're in trouble. Sure, there are workarounds to the threading issue - just export LD_ASSUME_KERNEL=2.4.19... only that'll trash your RPM database if you try and install certain RPMs with that flag set and I've only ever seen the FORCE_RPM_NPTL (and I'd have to verify that as I'm not at work right now) on one oracle site.
So that's pretty much the issues about Linux that have been raised with me in various environments. I hope it helps, and if you would like clarification on any of this, please let me know.
