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Monday, November 12 2007

Oracle VM: Funniest thing I read all day

Update: It's sillier and sadder than I thought. See below.

Today (2007/11/12), Oracle announced Oracle VM, their free competitor to VMware and (Citrix) Xen. A few months ago, Oracle announced "Unbreakable Linux", which is their re-branding of Red Hat Enterprise Linux. There are already many free Red Hat flavors, including CentOS, but not too many companies have built business models on attempts to take Red Hat support business away from Red Hat.

Oracle has. They made many loud claims of being cheaper and better than RHEL, while claiming this wasn't an attack on Red Hat. Red Hat was pretty quiet about Oracle Linux, but did point out that Oracle's claims to be actively fixing bugs in RHEL (supposedly faster than Red Hat does) without forking RHEL were impossible -- as soon as there's a fix which isn't available from Red Hat, that's a fork.

There's been a lot of ill feeling both ways over this, but of course neither company is willing to publicly and unambiguously badmouth the other.

Today we see another step in Oracle's (Linux) plan: Oracle VM is free, but Oracle offers paid support. The best part is this, though:

What is the difference between Oracle VM and the virtualization that comes bundled with Oracle Enterprise Linux?

As part of the Unbreakable Linux Support program, Oracle supports virtualization that is included with Oracle Enterprise Linux 5. Please note that Oracle products are not supported to run in that environment. Any customer who wants to deploy Oracle products in a virtual environment should use Oracle VM, and subscribe to Oracle VM support. Oracle customers should refer to MetaLink note 466538.1

Translation: We sell RHEL5 (which includes Xen as part of the base price) but we don't like it, because we want you to pay more for Oracle VM instead. We cannot realistically either break or drop support for Xen, even though we'd really like to, but we do get to chose what "platforms" we support Oracle on, so we'll support Xen, and Oracle on Linux, but not Oracle on Xen. Please don't think too hard about that one. It makes our heads hurt!

Update 2007/11/13: I missed the fact that Oracle VM is based on Xen. This means Oracle wants to sell you "Unbreakable Linux", but wants to charge an extra $500 to virtualize its own software on "Oracle's" Linux platform. I thought they were claiming Oracle VM was better than RHEL's VM, but that can't stand even cursory scrutiny, given that they're basically the same code. Additionally, their

• Three times greater efficiency than current x86 based server virtualization products;

has to be in relation to VMware which is not paravirtualized, but there is no way Oracle's brand-new Xen build is significantly faster than Red Hat's Xen kernel, running on Red Hat's Linux distribution.

Given that Oracle now recommends RHEL + Xen (from Oracle) as a platform for running Oracle Database & Applications products, Oracle's lack of support for running on RHEL + Xen (when purchased from Red Hat) looks -- I was going to say even more absurd, but this can't be an oversight, so it's just transparent corporate greed.

Saturday, September 8 2007

Red Hat 401: Deployment & Systems Management

I just finished RH401: "Red Hat Enterprise Deployment, Virtualization, and Systems Management". It's a 4-day course, given Tuesday-Friday of this week. The course is normally Monday-Thursday, with an assessment exam (EX401) on Friday. Had I known this, I probably would have taken the course with the exam -- I'd like to have that certificate. There are 5 tests (including EX401) to earn the exalted title of "RHCA", Red Hat Certified Architect.

The course covered several major areas:

  • Net booting (PXE, DHCP, & TFTP)
  • Kickstart (automated installation of RHEL)
  • Red Hat Network (rhn.redhat.com, a service hosted by Red Hat), Satellite Server (a local version of the service, which includes and installs net boot services), and Proxy server (a customized caching webserver which saves bandwidth and download time -- a subset of the full Satellite)
  • Building RPMs
  • Xen virtualization

Xen is very cool -- it's perhaps halfway between VMware and Solaris zones (containers), so more efficient than VMware but less than zones. Xen offers live migration between servers and supports RHEL 4.5 as a guest OS. With appropriate hardware (preferably recent Intel or AMD CPUs with hypervisor instructions), Xen can also virtualize Windows and earlier versions of RHEL. VMware is much more mature, but very expensive (easily more than the hardware it runs on for standard 2-socket systems), so this was a useful preview, even if we don't expect to use Xen much during the next year -- perhaps for Rockefeller's multi-user webserver, where we would like more isolation between users.

I was really there, however, to find out how to build custom RPMs for Rockefeller, manage them with custom RHN channels, and kickstart from a net boot server to streamline and automate installations.

Unfortunately this turns out to be surprisingly expensive, compared to what we pay to run RHEL. We normally pay $50/host/year for RHEL Academic Server, which is basically the Update & Management entitlements. This enables us to download patches from rhn.redhat.com (Update), and do a little bit more advanced stuff such as group systems in the RHN website (Management).

To use all the custom channels and kickstarting discussed in the class, we need a Red Hat Satellite Server (which costs about as much as all our RHEL Academic seats combined), and a $96 RHN Provisioning add-on Entitlement for each server. Combined, these would quadruple the amount we pay Red Hat annually for our servers, and I'm not at all convinced it would be a worthwhile investment.

We may instead get a Red Hat Proxy Server, which provides custom channels and costs much less than the full Satellite, and build our own kickstart server, forgoing all the Satellite features. This would be a shame, but might turn out to be the best compromise.

Another problem is that the RHN/Satellite back-end is RHEL4AS only -- it doesn't run on RHEL5, and it doesn't coexist well with any other services. This is a larger Red Hat problem, rather than specific to the class, but it meant the class was a mixture of RHEL4 and RHEL5, and made things more complicated.

It's enough to make one seriously consider CentOS, is a rebranded free version of RHEL. We don't want to do that, though.

Paul, our instructor, was full of excellent tips on better ways to work with RHEL. Unfortunately, I avoid many of these (decidedly useful) techniques, since they only work on Linux (or only RHEL), and I generally stick to things common to Linux, Solaris, and Mac OS X. The neat stuff Red Hat has added recently, which he was excited about, would make my RHEL work more efficient at the expense of having to keep track of the RHEL way and the non-RHEL way. Those commonalities are essential for me.

Still, I learned a lot of useful stuff about RHEL, and now just need a chunk of time to set up a kickstart server and decide how to do DHCP -- our DHCP scopes are managed by the Network Group, and we need a way to set up and manipulate kickstarting without asking them to make multiple DHCP & VLAN changes. I have some ideas for how to automate and customize the kickstart process, which I'd really like to test and implement.

Saturday, August 11 2007

Chris Pepper, RHCE

I passed the RHCE exam, hooray!

This was much easier than becoming Dr. Pepper, and much easier & safer than becoming Sgt. Pepper.

Friday, August 10 2007

Took the RHCE Exam Today

I spent Monday to Friday this week in RH300, the Red Hat Certified Engineer Rapid Track Course; today (Friday) was the exam. I believe I passed -- they should email my final results by Wednesday. In reality, I took the test as much for the RHEL5 update as for the certification.

I was concerned about problem solving with no Internet access, no access to another system (in real life we almost always have another live system to check things out, as opposed to troubleshooting grub on an unbootable system without working man, which was a problem in class), and no ability to discuss with co-workers, but it's not an exam about how well you can find answers on The Google, so this was the only realistic way to do it.

Wednesday, May 16 2007

rpm -e --allmatches

I was deleting some unneeded Samba RPMs today, since they're vulnerable to a security bug, and hit a snag on a 64-bit machine, where rpm was too stupid to handle the presence of both 32-bit and 64-bit RPMs. The error was 'error: "samba-common" specifies multiple packages'. The solution is simple but obscure: Add "--allmatches", as in "rpm -e --allmatches".

As it turns out, I can't really remove samba-common anyway, because it's required for kdebase, which is required for half the RPMs on the system, but now at least I know the trick for next time. RPM really needs to deal with multi-flavored packages better.

Thursday, May 4 2006

Network Monitoring with ping

For long-term low-overhead network monitoring, I came up with the following (note that the ping arguments are for Mac OS X ping -- Linux syntax is a bit different).

Put these into cron (with crontab -e):

0  0   *   *   *   ping -c 144 -Q -i60 www.speakeasy.net >> ~/public_html/dsl.log
*/10    *   *   *   *   date >> ~/public_html/dsl.log

And watch the status something like this: tail -f ~/public_html/dsl.log

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