[newly cross-posted into the centos mailing list]
On Thu, 6 Jul 2006, Stephen John Smoogen wrote:
I understand that the following products [RHEL v the CentOS rebuilds] differ in price based on the extend of support. Apart from that, is there any other difference (i.e. performance, kernel stability etc)?
CentOS is an outgrowth of early efforts of Lance Davis in the UK, and has been consciously shaped, structured and recruited by me and a couple of other admins at the end of the RHL series to tap 'the best and the brightest' of the pool of non-Red Hat RPM based distribution developers to build a professonal grade 'community' RPM based successor to RHL; some of us ran the cAos-1 high performance cluster oriented distribution creation to explore some packaging and buildsystem issues, and to build community, tools, and approaches.
Once CentOS was viable, it spun off from being a cAos sub-project into the free-standing project it is now; in Enterprise Linux community rebuild space, it has essentially displaced WhiteBox (in part due to the loss of momentum which last years hurricane inflicted on New Orleans, and John Morris' fine effort), had a friendly merger in of David Parsley's Tao, and regularly has binary updates in place and more available than the upstream, due to a massive mirror pool, and a smart, geo-location aware update mirror dispatching system.
I don't think this is really on-topic for the Dell Poweredge list.
dunno -- one is commercial and carries front end SLA's, a certification program, etc, some non-freely available source software, and costs; the other is community, organic and consciously without SLA's and the rest, and is not. Each runs just fine on Dell hardware (which I have been using on Dell PowerEdge kit for many, many years, in specing and delivering complex networks to customers) [btw, Matt, et al., thanks for the XPS series -- it makes a stable, sweet and scaldingly fast Linux lovin' desktop]
The differences between CentOS and RHEL are mainly in the type and level of support you get from each. CentOS support is whatever you get from IRC, mailing lists or what you will pay a consultant to answer.
The main CentOS IRC channel #centos on irc.freenode.net consciously tries to mix relentlessly On Topic, fast, technically accurate, work safe _teaching_ replies [based loosely on a Socratic method], with a bit of 'floorshow' -- I am one of the 'ringmasters' most weekday US business hours, and we have developed a cadre of 'regulars,' each of whom demonstrates advanced RHCE level expertise in addressing questions in real time from all comers.
The mailing lists and IRC will not spoon feed an answer and will tell a person that they are an idiot directly versus telling their bartender at the end of the shift.
(smile) part of the floorshow design [the channel op's try to make the channel the one tab in the audience' IRC client left open and on top, so that less skilled admins will 'idle and "read the mail"' in it, to see what happens next, and also soak up both good BOFH skills and accurate RHCE type training ;) ]; a careful observer will note that Off Topic participants are pointed to other more appropriate venues for their inquiries, and cautioned several times before any 'festivities' occur. [I cc the centos list, as a way to publicly thank those participants]
For as much as I can tell, the base Centos is RHEL recompiled with the same options etc. and the Red Hat trademarks removed. If your organization does not need any support then CentOS can be a good match.
CentOS are very cautious to be 'very correct' as to respecting intellectual property rights in the rebuild.
It is also correct that we expressly strive to match build environments, and use 'ldd' and other tools to verify as close as possible binary compatability to the upstream's binary offerings as we can [some recent packages have been built with non-released compiler variants at the upstream 'PNAELV', and so there are minor known divergences from time to time, which thus far have not affected performance]; we upstream issues, and proposed fixes from the CentOS Bug tracker into Red Hat's Bugzilla regularly, and some of the core are well known participants in the 'Fedora' project RH runs.
'performance, kernel stability' and the rest should be identical - if a deviation is suspected, I hope for and want to see a bug filed; we will track down a substantiated issue reported to our bug tracker; we maintain a reporting address, and respond to security inquiries confidentially and promptly; we have the expected mailing lists, website, wiki, forums, and the rest. Sometimes our art is criticized as not as flashy as some other distributions, but the distribution is not looking to win style shows ;)
Commercial support is available from several of the core CentOS developers' companies, on an a la carte basis.
- Russ Herrold