SLES or RHEL?
Or, How I Learned to Stop Worrying, and Love the Penguin
The Penguins Are Coming
When SAP announced HANA, they also announced it would only be available on Linux. As I understand it, that was a major departure from the past. Previously, you could roll out SAP products on a variety of OS and database platforms.
Now, your choices are limited to the two major commercial Linux distributions:
SuSE Linux Enterprise Server (SLES)
RedHat Enterprise Linux (RHEL)
Which one should you use? It’s a question that can quickly devolve into a religious war amongst technical staff.
If you are leading the migration to SAP HANA for an organization, and you’re facing this question, I have some quite secular thoughts to share. My goal is to help you make the decision, not tell you what decision to make.
A Brief History Of Time
If you set your Wayback Machine to the late 1990s, I was a Novell NetWare sysadmin, happily delivering reliable file, print and E-mail services to a user population of less than 1000, in a small data center. I spent more time trying to get Windows workstations to be as reliable than I spent in the server room.
But I could see the writing on the wall for NetWare. At the time, Novell was financially healthy, but they were bleeding talent, and had badly bobbled both their sales channel and relationships with ISVs. This was also about the time a post in a Usenet newsgroup announced something called Linux.
I’d had prior experience with DEC Ultrix / MicroVAX, and Linux was too nascent, so I decided to re-enter the UNIX world via SunOS/Solaris on SPARC. One thing led to another, and by the early 2000s Linux had matured, Novell had purchased SuSE, and I began to get into Linux.
I started with early distros, like RedHat Linux 7 (a pre-cursor to RHEL) and SuSE Linux 6 (a pre-cursor to SLES); my earliest Enterprise implementations were SLES v9 and RHEL v2.1. For 12 years, I worked nearly exclusively in RHEL, from RHEL v3 to v7. In the past 2 years I’ve returned to SuSE, engineering SLES v12 and v15 to support an SAP HANA 2.0 environment.
As you can see, I’ve lived in both worlds. I have a soft spot for SLES due to the Novell connection, but there are a number of aspects of RHEL that I prefer to the SLES equivalents. My view on SLES vs. RHEL is holistic, not partisan. For me, they are dialects, similar to Spanish and Portugese. If you know one, you’ve already got a grasp of the other.
My Opinion
So, if you are pondering which Enterprise Linux to underpin your HANA rollout, what should you consider?
Start with your organization - does it already have a significant implementation of one distro? If so, you should definitely give that weight. The larger that particular distro looms in your existing environment, the more weight it should have.
If you’re in, say, an AIX shop, with little or no existing Linux presence, then that’s of no help.
If your path is still unclear, then I suggest you consider supportability as your next criteria. SuSE and SAP are headquartered less than 50 miles from each other. With the proper SAP support contracts, SAP will take SLES issues directly to SuSE; if you’re on RHEL, you’ll end up doing that yourself. Right or wrong, good or bad, everything I have seen leads me to conclude that SAP favors SuSE (notably, the current SuSE CEO is the former SAP CFO). If your environment is SAP-focussed, then that may drive your decision towards SLES.
If you’re considering (or are already committed to) platforming on PowerPC, I have not seen a significant difference in the support of either distro. The challenges are (largely) the same.
Ultimately, there is no “right” or “wrong” answer. It’s a decision that must be driven by your organization, any existing Linux footprint, and the role of SAP within it.