David hello, Because this has the potential to be a long debate, allow me to start with few quick notes - PROS: All the statelite pros you can think of - - single image to manage (no puppet etc.). - Small RAM footprint (essentially equivalent or close to equivalent to statefull) - Unlike stateless, no RAM 'penalty' on image size On top of that I would add - Ones deployed, easy management - much of the management burden simply not there.
CONS: - Harder to setup and deploy - not a lot of installations use statelite so naturally, more bugs can be found and less customer experience. - NFS traffic - you need the right infrastructure to provide sufficient performance - the infrastructure is yet another component that can fail. Usually you would like to have HA so this is another layer that add complexity. We used GPFS cNFS as the mechanism to ensure HA to hold both the image and the node specific files. This turned out to be a solid solution and proved to be reliable. We used the service nodes as the GPFS cNFS servers, with /install mounted as GPFS volume to all of them. This way we could also export the image itself with cNFS. Bottom line - before we've deployed our first statelite cluster I was a bit sceptic, but this is actually working very well and I would recommend it (well, depends on the specifics, of course). I am pretty sure you would like some more details so just let me know and I will be happy to provide. Gilad Berman HPC Architect Lenovo EMEA +972-52-2554262 gber...@lenovo.com Lenovo.com Twitter | Facebook | Instagram | Blogs | Forums -----Original Message----- From: David D. Johnson [mailto:david_john...@brown.edu] Sent: Monday, April 3, 2017 7:22 PM To: xCAT Users Mailing list <xcat-user@lists.sourceforge.net> Subject: [xcat-user] statelite vs stateless We have several hundred stateless compute nodes, but we’re starting to wonder if we should be using statelite provisioning instead. The primary issue we would hope to address is having a place to save Kerberos host credentials. Of course we could do this at boot time using some kind of post install script (anybody have one they’d be willing to share?). Are there other advantages that any of you folks have found to state-lite that would make me want to convert? Do you use local storage or something like GPFS or NAS to hold the node-specific partitions? Thanks for any advice / suggestions / caveats! Regards, — ddj Dave Johnson Brown University ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ xCAT-user mailing list xCAT-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xcat-user ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ xCAT-user mailing list xCAT-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xcat-user
