Article 34042 of comp.sys.sun.hardware: Path: matra.meer.net!tera.mcom.com!news.Stanford.EDU!agate!howland.reston.ans.net!news.sprintlink.net!in2.uu.net!svc.portal.com!news1.best.com!shellx.best.com!usenet From: Rick Meneely Newsgroups: comp.sys.sun.admin,comp.sys.sun.misc,comp.sys.sun.hardware Subject: Re: What is your dream NFS server ( < $100K )? Date: 17 Sep 1995 06:26:39 GMT Organization: Ouroboros Adventures Lines: 108 Message-ID: <43gf2v$6jn@shellx.best.com> References: NNTP-Posting-Host: rick.vip.best.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable X-Mailer: Mozilla 1.1N (Macintosh; I; PPC) X-URL: news:steve-1409950724310001@137.79.37.121 Xref: matra.meer.net comp.sys.sun.admin:64360 comp.sys.sun.misc:24410 comp.sys.sun.hardware:34042 steve@tsunami.jpl.nasa.gov (Stephen Mitchell) wrote: >What would your ideal machine/configuration be in this situation, given >that you can only spend between 50 and 100K? NFS accelerator hardware? I have used Auspex, Sun Sparc-10s and Sparc 1000s and NAC 450 and 1400 systems as NFS servers. I have no hesitation in which I pref= er - NAC (Network Appliance Corporation). Why buy a Network Appliance server? ----------------------------------- * Reliable - I have never lost data on an NAC. Uptime is excellent and response is fast. * Ease of administration. As the system ONLY provides NFS service it only contains commands directed towards NFS. I mount all my NAC boxes root directories on my Sparc 'admin' machine so I can easily do most maintanence without logging in to them. This is the way you edit system files, etc. Upgrades are simple - About 1-2 minutes to install the OS and another 90 seconds to boot the system. I tell my users to expect a slight delay at X o'clock while the system is being upgraded, no need to logout. Try to do this on a Sun or Auspex (or ANY UFS based system) - you can't. Virtual file system and striping. Yes most NFS boxes will do both of these, but YOU have to tell it what and how. You can easily shoot yourself in the foot with many other systems - "Well this disk is no longer hot swapable because you striped your array in X manner" - No Thanks. Backups can be done on-line and still be consistent. Take a snapshot (takes 2-3 seconds on a 24GB system) and back it up. Now delete the snapshot. Note that a snapshot only creates a 'consistency checkpoint' which does not require copying files only pointers (small overhead). * Boot time - ~90 seconds. This is because filesystems are always consistent. NAC does not use UFS (Unix File System) which are not consistent and therefore tries to patch itself back together with 'fsck' each time the system boots (and reboots whenever it makes a fix). NAC uses WAFL (Write Anywhere File Layout) which is always consistent and is optimized for NFS, especially NFS writes. * SNAPSHOTS - This is unique to NAC boxes due to WAFL. Deleted files are kept on-line and can be recovered by the USER until they are 'aged' off the system. This has been a MAJOR LIFESAVER several times. Not only can the user recover the data him/her self, but the data is recovered faster and is more current (whenever the last snapshot was taken - I generally take 3 snapshots a day and keep 48 hours worth on-line). * RAID level 4 - Level 4 means that 1 disk is a parity disk. Most companies do not offer level four because it can be a bottleneck if you have to write to a particular disk each time. WAFL and an NV-Ram cache remove this as a bottleneck. The disks are written to when either the cache is half-full or a maximum delay is reached. * NFS OP caching NOT simply file I/O Caching. This means that the NAC can ACK the NFS command as soon as the command/data is cached (another advantage of WAFL and NV-Ram). UFS based systems, even if they have an NFS cache must wait for the filesystem to break the data into blocks and allocate a place for it on disk - THEN AND ONLY THEN may they send an ACK. * Scalable - What happens if you buy a large and expensive Sun or Auspex system and you REALLY need another one but it's so expensive to make that jump. When I was administrating an Auspex we were always buying expansion cabinets (at ~$10K each). Try telling a department manager that he needs to chip in several thousand extra $$ so he can get that 2GB disk online. NAC scales in small increments and with each NFS filesystem comes the resources to access that data so you won't see you performance degrade as you add filesystems. We currently seem to be going towards an NAC box per function or group. We have one for home accounts another for project data, etc. If the /home1 mount gets full we simply buy another for /home2, performance will not degrade and the cost is far more reasonable than the cost of another Sun 1000 or Auspex. * Dedicated - If you get a system that can also do standard unix operations, people will use it for that. People will log into your Sun or Auspex to run their simulation/compile, etc. On an NAC that won't happen - rlogin is not supported only a single telnet session, which is all you need for administrative purposes. I am a firm believer in getting the right tool for the right job. If I want a compute server I'll get something with CPU performance, if I want an NFS server I'll look for NFS-OPS. Why NOT get a Network Appliance server? ---------------------------------------- * If you have software that uses non-NFS file locking. Such as Cadence's 'composer' software. * If you have software that expects to be able to do rpc calls to the server such as Atria's ClearCase software. Note you CAN get ClearCase to work by having a proxy server but I find that an ugly solution. I have never used a Falcon Raid system. They appear to have a nice cost sensitive solution. If you were looking for a system at about $15-$20K I would suggest you take a look but if you can afford ~$60K for a fully loaded NAC 1400 I'd suggest it instead. Well that's my long-winded two-cents worth. -Rick