Primary survey results: Mission Critical Linux
To: Everyone interested in Linux!
Initiated from the 'Linux Mission Critical Systems' mailing list is a project to document successful existing systems which have a large load and are up 24 hrs/day. Already we have received a rich amount of information!
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Getting to the questionnaire:
Mission Critical Linux - answers2\30
Privacy: level 1Current kernel: 2.0.21
Oldest kernel: 0.99
Used Slackware 3.0, rated fairUsed Red Hat 3.0.3, rated goodNumber of Linux servers: 6
Total number of Un*x servers (including Linux): 7
Number of Un*x clients: 3
Number of DOS/Windows clients: 4
Average uptime: 30-40 days
Longest uptime: 78 days
Average E-mail messages/day: ~200
Maximum E-mail messages/day: ?
Average http hits/day: 100000
Maximum http hits/day: 150000
WWW server: Apache
Using XFree86Using We're testing different SQL db's right now
Linux information rated good
Reliability rated good
Robustness rated good
Performance rated good
Hardware support rated good
Software support rated fair
Project support rated fair
Distributor support rated fair
News group support rated fair
Installation procedures rated good
Upgrade procedures rated good
Un*x compatibility rated good
Un*x 'look & feel' rated good
Sharing the network with other Unix OS's rated fair
Sharing the network with Windows95 rated good
Contact with fellow Linux administrators rated poor
WWW sites: different sites all over the web.
Netnews: comp.os.linux.*, comp.security.unix
Books: NAG
Other: HOWTO's and FAQ's
Q: A description of the work in relation to the Linux servers
A: Keep everything running, and installing new software once in a while.
I also develop mainly CGI programs on the servers.
Q: A description of the site
A: The purpose is to provide webhotel, webdevelopment and mailserver for our customers.
The programmers use Linux machines, and the sales persons/graphics developers use Win
95 and a single SGI
Q: What is the most critical aspect of your site?
A: Uptime Network access Integration with other Linux
machines and Win95 (for the developers) Backup
Q: What is the history of the site?
A: Has in 1 year grown
from 1 server, 1 Linux client + 1 Win 3.11 client to the specified size above.
We started with Slackware, but have migrated to RedHat. The reason for this is purely
the RPM function in RedHat. Slackware is a bitch to upgrade correctly.
Q: Why and when did you choose to use Linux?
A: I have used Linux for 3 1/2 years now, and there was no real choice when starting a
WWW company. Definitely no Windows on the servers - only Unix. And since I already had
a lot of experience in Linux, the choice was given beforehand. Another reason is
reliability and availability of great system software. Another reason is the fast
debugging of kernel code and other critical software. Thanks to the Linux community.
They are doing a great job.
Q: Did you experience any failures or hurdles?
A: None. Everything was nice and easy.
Q: Do you intend to expand the use of Linux at your site, and how?
A: Yes and no.
All new clients for programmers will be Linux machines.
The server park is big enough as it is with Linux machines. We will buy us a Sun or
SGI server soon, because of the unfortunate lack of commercial databases (mainly
Oracle)
Q: How do you compare Linux with other Unices you use and have used?
A: It is much faster as a client compared to Xterms up agains a
big Sun/SGI.
The overhead waste compared to other OS's on Intel machines is very low. Linux gives a
lot of extra power, that other OS's waste on who knows.
Q: What commercial software packages do you use with Linux, and are you satisfied?
A: Caldera's
WordPerfect package is great, and we are very satisfied with it.
We are looking forward to coming Java software like Corel Office.
Q: What have you done to increase the robustness of Linux at your site?
A: Decentralize different tasks. Backup server is not on the same machine as mail, not on
the same machine as http server and so on.
Linux has a weakness on very heavy loaded systems (load 10+), when it starts killing
random processes to get the load down.
Q: Are you using any special backup procedures?
A: Mirroring disks, rotating
backups of system and client areas. We have the 7 weekdays on backup, then the last 4
weeks, and then monthly backups. Standard thing.
Q: Are there security holes in Linux you want to warn about?
A: Just watch it when
using a lot of foreign CGI (not produces in house). You can very easily create holes
when using system commands in PERL as an example.
Nothing else, when you're keeping yourself up to date on system security upgrades
(like sendmail)
Q: What new technologies are you expecting for future Linux development?
A: Not that much hardware. Hopefully better NFS speed.
It s*cks in comparison to other Unix's.
Q: Are you excited about the future of Linux?
A: Yes. I hope it catches on in
the commercial software business as an _REAL_ alternative to Solaris and other Unix's.
If the software is there, then Linux has a bright future. If not, then it dies slowly.
Q: Do you have further comments, or suggestions for Linux administrators?
A: Nope.
Thomas Lund
Mission Critical Linux - answers2\33
Privacy: level 1Current kernel: 2.0
Oldest kernel: .99
Used Slackware 3.0.3, rated goodUsed Red Hat 3.0.3, rated goodUsed Caldera 3.0.3, rated goodNumber of Linux servers: 1
Total number of Un*x servers (including Linux): 1
Number of Un*x clients: 1
Average uptime: 20 days
Longest uptime: 50 days
Average E-mail messages/day: 4
Maximum E-mail messages/day: 10
Average http hits/day: 40
Maximum http hits/day: 200
WWW server: Apache
Using Accelerated XLinux information rated good
Reliability rated good
Robustness rated good
Performance rated good
Hardware support rated fair
Software support rated good
Project support rated good
Distributor support rated fair
News group support rated good
Installation procedures rated good
Upgrade procedures rated good
Un*x compatibility rated good
Un*x 'look & feel' rated good
Sharing the network with other Unix OS's rated good
Sharing the network with Novell rated fair
Contact with fellow Linux administrators rated fair
Netnews: comp.os.linux.misc
Magazines: linux journal, sysadmin
Q: A description of the work in relation to the Linux servers
A: I maintain a linux box which is used predominantly for running
molecular biology software, but which is also used to supply
short term mail and internet facilities for transient scientists
who come through our lab.
Q: A description of the site
A: Purpose: tos supply a good cheap robust X server to run a range of molecular
biology programs such as gcg, prophet, as well as general software such
as spreadsheets, word processing and graphics necessary to proces
and publish scientific data.
Q: What is the most critical aspect of your site?
A: Undoubtedly the need for a stable, reliable platform for processing
my scientific data without undue risk of loss.
Q: What is the history of the site?
A: I set up the site when i moved to the National Institutes of Health
in maryland from Australia. it has been running for over a year, with
minimal glitches.
Q: Why and when did you choose to use Linux?
A: I was very enamoured by the open and collaborative nature of Linux.
I was fairly concerned about the predominance of a few large software
companies, and the inhibitory effect on the software market. Linux worked,
gave vastly superior performance out of my old 386 for some molecular biology
stuff I was doing, so i made the decision to commit to it and I have not
looked back.
Q: Did you experience any failures or hurdles?
A: The early slackeware versions were hard to upgrade. The learning curve was somewhat
steep, but there was always plenty of good natured support among the
people of the net.
Q: Do you intend to expand the use of Linux at your site, and how?
A: Yes, various other scientists have expressed interest, and I have already
helped set up another box. I will probably set up another just as
an X server sometime in the next 2 weeks.
Q: How do you compare Linux with other Unices you use and have used?
A: I like it. My only other experience is with SunOs, and it is certainly
comparable. i am sure that highly "stacked" SunOs comes with more toys
and goodies, but at the basic level, Linux kills it. (eg C/C++, fortran) as
standard.
Q: What commercial software packages do you use with Linux, and are you satisfied?
A: Calderas internet office suite, and MetroXs open Gl.
I must say that both of these companies have been somewhat of a disapointment
for me. Caldera indulges in "release in tiny dribble"-ware - so I find
myself paying for the priveledge of supporting them early on by having
to buy everything at premium dollar. By my early support, I supplied the
revenue stream which allowed them to develop their product profile. I
notice with increasing disapointment that they bundle their products
and that I always have to buy in at top dollar. This makes it hard to
persuade those where I work that Linux is cost-effective solution. Eg-
I spent $350 on internet office suite. Now Wabi is out, at $199. Caldera
offer a deal on office suite and wabi that knocks off ~$150 bucks - but
I have to buy in at $199. This is a most unfortunate pricing strategy in
that there is no loyalty to old customers. Also they screwed up my name
on their database, so I dont get posted news of updates, etc. A price break
on bundled software, and some follow up on new product literature would be a big help.
As for MetroX- I waited 7 months to get their open Gl. It was supposed
to come with hardware support for matrox cards. To date this support has
not materialised. frankly, it was a waste of time.
I was delighted to support companies that supported Linux- I looked
around to do this. I feel in the corporate linux world that there
is too much of a feeling that " they should be bloody grateful that we
suppoert their weirdo operating system". A little more professionalism
would no doubt not go amiss.
Q: Are you using any special backup procedures?
A: Taper, little else
Q: Are you excited about the future of Linux?
A: Yes, in time I think that it has the potential to evolve into the
prefered o/s. I feel that Microsoft is already finding "product lag"
in that people see little reason to upgrade from 3.1 to 95 to NT. At
the moment linux cant compete, microsoft is growing too fast, but there is IMHO
some sign that this is slowing down. If linux can survive and keep its
usefulness, get a standard easy GUI that is really intuitive (and there)
certainly are some of those, just that they are a bitch to set up, it may
compete most favourably one day.
Leon Harris
Visiting Fellow
Mission Critical Linux - answers2\35
Current kernel: 2.0.22
Oldest kernel: 1.0.x
Used Slackware 2, rated fairUsed own 2, rated fair
Number of Linux servers: 3
Total number of Un*x servers (including Linux): 6
Number of Un*x clients: 50
Number of DOS/Windows clients: 30
Other clients: 20
Average uptime: 40 days
Longest uptime: 200 days
Average dial-in users/day: 1
Average http hits/day: 200000
Maximum http hits/day: 350000
Average FTP Mb/day: 10
WWW server: Apache
WWW server: squid
Using XFree86Participated in Linux kernel developmentParticipated in Linux network utility developmentParticipated in Linux other utility developmentUsing Mini SQL (msql)Linux information rated good
Reliability rated good
Robustness rated good
Performance rated good
Hardware support rated good
Software support rated good
Project support rated good
Distributor support rated good
News group support rated good
Installation procedures rated good
Upgrade procedures rated fair
Un*x compatibility rated good
Un*x 'look & feel' rated good
Sharing the network with other Unix OS's rated good
Contact with fellow Linux administrators rated good
WWW sites: http://www.linux.org/
Netnews: comp.os.linux.*
Q: A description of the work in relation to the Linux servers
A: System and Network Managment, Application Development
Q: A description of the site
A: Nuclear physics laboratory (15 MV linear accelerator).
Main purpose of our computer systems is data acquisition for
nuclear physics experiments, and replaying of the data.
Also we provide computer services for some physics institutes
of both Munich Universities, as well as some general services
for the Garching Campus (DNS and WWW Proxy)
Q: What is the most critical aspect of your site?
A: During experiments (almost always!) system must be stable.
Q: What is the history of the site?
A: Originally we used a Digital DECsystem 10 (36bit machine). After
phasing out this propietary system 7 years ago, we switched to
Unix Systems (server and Workstations). Linux is in use now
since two years with great success.
Q: Why and when did you choose to use Linux?
A: Two years ago, because it is free. First we used it for an Modemserver,
later on we started to use it as workstations, since an year, we use
it also for NFS and WWW serversystems.
Q: Did you experience any failures or hurdles?
A: There was some trouble with NFS, which we solved together with
Olaf Kirch, who maintains the nfs Server.
Q: Do you intend to expand the use of Linux at your site, and how?
A: We expand the size of our main Linux server (faster CPU, more memory,
mor disk). Also there will be more Linux workstations (currently already
over 20)
Q: How do you compare Linux with other Unices you use and have used?
A: It compares very well. In some parts it is even more elaborated.
In other parts some things are missing. Currently there is no
File/Record Locking in Linux NFS. Also there is currently no Logical
Volume Manager for Linux.
Q: What commercial software packages do you use with Linux, and are you satisfied?
A: Currently none, but we are evaluating StarOffice, as well as
an Fortran Compiler from SNI
Q: What have you done to increase the robustness of Linux at your site?
A: I do not use supercheap Clones, only PCI Motherboards from
vendors with good reputation, also we use only SCSI disks.
Q: Are you using any special backup procedures?
A: Own script written in TCL/TK, which uses dump/rdump
Q: What new technologies are you expecting for future Linux development?
A: Kernel based nfsd, support of file/record locking over nfs,
Logical Volume Manager.
Q: Are you excited about the future of Linux?
A: Yes
Q: Do you have further comments, or suggestions for Linux administrators?
A: Don't use (E)IDE
Klaus Steinberger
Dipl. Ing (FH)
Klaus.Steinberger@Physik.Uni-Muenchen.DE
Accelerator Lab, University Munich
Mission Critical Linux - answers2\36
Current kernel: 2.0.10
Oldest kernel: 1.3.97
Used Red Hat 4, rated goodNumber of Linux servers: 6
Total number of Un*x servers (including Linux): 2
Number of Un*x clients: 500
Number of DOS/Windows clients: 4000
Other clients: 3000
Average uptime: 40 days
Longest uptime: 120 days
WWW server: Apache
Participated in Linux network utility developmentLinux information rated good
Reliability rated good
Robustness rated good
Performance rated good
Hardware support rated good
Software support rated good
Project support rated good
Distributor support rated good
News group support rated good
Installation procedures rated good
Upgrade procedures rated good
Un*x compatibility rated good
Un*x 'look & feel' rated good
Sharing the network with other Unix OS's rated good
Sharing the network with Windows NT rated good
Sharing the network with Windows95 rated good
Magazines: linux journal
Q: A description of the work in relation to the Linux servers
A: System administrator.
Q: A description of the site
A: Print services for mac, pc, and unix.
Q: What is the most critical aspect of your site?
A: keeping the print jobs moving
Q: What is the history of the site?
A: Used to be one Axil 235 running SunOSdoing the unix printing. Now we have 11 production servers and 2 developement servers 10 of which are running linux. We will be getting more servers as soon as budget allows. Two maybe all three of the servers that are still running sun OS are scheduled to be converted to linux as soon as time permits.
Q: Why and when did you choose to use Linux?
A: Full source code. Cross architechure support
Q: Do you intend to expand the use of Linux at your site, and how?
A: Yes all the print servers will be running linux and the number of print servers will continue to grow. Other production services such as DNS will possibly be converted.
Q: How do you compare Linux with other Unices you use and have used?
A: = or >
Q: What commercial software packages do you use with Linux, and are you satisfied?
A: Netscape. Yes
Q: What have you done to increase the robustness of Linux at your site?
A: Several bug fixes/modifications to lpr
Q: Are you excited about the future of Linux?
A: Yes
Ben Woodard
Sysadmin
bwoodard@cisco.com
cisco systems
Mission Critical Linux - answers2\37
Current kernel: 1.3.59
Oldest kernel: 1.0pl19
Used Slackware 2-3.x, rated goodUsed Red Hat 3.x, rated fairUsed Caldera 1.0, rated goodNumber of Linux servers: 14
Total number of Un*x servers (including Linux): 21
Number of Un*x clients: 6
Number of DOS/Windows clients: around
Other clients: 10-15
Average uptime: 45 days
Longest uptime: 187 days
Average dial-in users/day: 50
Average E-mail messages/day: 5000
Maximum E-mail messages/day: 10000
Average http hits/day: 1000
Maximum http hits/day: 2000
WWW server: NCSA
WWW server: Apache
Using XFree86Participated in Linux network utility developmentParticipated in Linux other utility developmentUsing Postgress (mpsql)Using Replicated servers, in-house tool provides capability
Linux information rated fair
Reliability rated good
Robustness rated good
Performance rated good
Hardware support rated good
Software support rated good
Project support rated good
Distributor support rated fair
News group support rated good
Installation procedures rated fair
Upgrade procedures rated poor
Un*x compatibility rated good
Un*x 'look & feel' rated good
Sharing the network with other Unix OS's rated good
Sharing the network with Windows NT rated fair
Sharing the network with Windows95 rated good
Sharing the network with Novell rated fair
Sharing the network with OS/2 rated fair
Contact with fellow Linux administrators rated good
Netnews: comp.os.linux.development.apps, comp.os.linux.development.system
Books: General Unix and Development books, since Linux is such a standard now
Magazines: The Linux Journal, I have authored several 'Best of Tech Tips' there as well
Other: Experience, Experience, Experience
Q: A description of the work in relation to the Linux servers
A: I am the Senior Systems Analyst for BRT Technical Services Corporation.
My duties cover all aspects of our clients' varied needs. Linux has
been my 'Swiss Army Knife' - able to cover almost any need or repair
any problem.
Q: A description of the site
A: We are a technological consulting firm. Our own use is somewhat
limited (we only use two servers, for example) in comparison to what
our clients have. We services the financial and commercial districts,
so we have a high need for robust, fault-tolerant servers. Linux
always comes through, even much more so than a commercial platform
such as SCO Unix. For something like SCO, you find 'workarounds'
on their Web site. For Linux, the same problem is immediately fixed
and never seen again. This is CRUCIAL to our operation!!!
Q: What is the most critical aspect of your site?
A: The servicing of user requirements for storage space and financial
services. We do quite a bit of custom database programming as well
as general networking and intranetworking.
Q: What is the history of the site?
A: Depends on the client.
Q: Why and when did you choose to use Linux?
A: I had quite some experience with the platform in college, and decided
it aptly covered our needs in-house. We examined the system more
closely to see the base of available software, and realized the other
capabilities the OS and its software base (Apache, Samba, etc) provide.
Q: Did you experience any failures or hurdles?
A: Of course, but they were FAR easier to cope with than those we had
with SCO, UnixWare, and several other platforms. In general, I've
found that ESPECIALLY for 'strange' or 'esoteric' applications, the
Linux servers we have used have been MORE versatile simply because of
its origins and current developer base.
Q: Do you intend to expand the use of Linux at your site, and how?
A: Of course. Like I said, it is now my Swiss Army Knife. I have used
it to replace servers, to augment them, to add capability to existing
clients, and to provide initial services to new clients.
Q: How do you compare Linux with other Unices you use and have used?
A: It far exceeds their capabilities. It is much more efficient,
much MUCH MUCH more stable (please, I CANNOT exxagerate this enough!)
and far more capable. We have experience with HP/UX, SCO, UnixWare,
DEC Unix, AIX, and Solaris. Give me Linux any day. I wish it had a
slightly better NFS implementation, but I take my lumps and call it
sugar.
Q: What commercial software packages do you use with Linux, and are you satisfied?
A: Very rarely will we use a commercial package. We tend to use the
servers as file, print, and intranetworking servers, and the free
software base easily covers that corner. I have used Caldera with
some personal success, but rarely use commercial packages under Linux
in a commercial environment. We almost always resort to an in-house
solution before we pursue that avenue.
Q: What have you done to increase the robustness of Linux at your site?
A: Generally, the only necessary actions have been to install backup
Web/DNS/etc servers, increase the memory and capabilities of the
general hardware platforms, and add RAID capabilities in the form
of hardware solutions. I am not happy with md or its capabilities,
but it is so new now that I don't expect anything worthwhile out of
it yet.
Q: Are you using any special backup procedures?
A: Rarely more than a nightly tape stream. We design server hardware to
be fault-tolerant and redundant. On occasion a server will back up
other servers, but for the most part, we have very little trouble
with server failure. We use only the highest quality components so
we have less of a worry. For example, we will generally purchase
a Hewlett-Packard Netserver before we build a home-grown server
system.
Q: Are there security holes in Linux you want to warn about?
A: I generally watch the newsgroups and security-based mailing lists.
CERN is excellent about discovering security holes, and other
operating systems have far worse problems than Linux. Any Unix
administrator must take it upon him/herself to protect his/her site(s).
Nobody will do it for them, and if there are security holes, well,
I've fixed all I've found, and I think at least I have everything that
OTHER people know about.
Q: What new technologies are you expecting for future Linux development?
A: I would like to see the 'md' kernel support greatly enhanced. I would
like to see more support for new devices, but that always happens
anyway. IPv6 is a must, but is already in development. What can I say?
Everything I've ever wanted has either been already there, or under
active development.
Q: Are you excited about the future of Linux?
A: Absolutely. How could I not be with a usage like this?
Q: Do you have further comments, or suggestions for Linux administrators?
A: Read EVERY document you get. At least remember what it was about
and where you got it. I removed too many documents I didn't think
I'd ever use, only to discover too late...
I think a general Unix background helps somewhat, but not if it's AT&T
based. Practice makes perfect, and don't ever give up.
Chad Robinson
Senior Systems Analyst
chadr@brttech.com
BRT Technical Services Corp.
Mission Critical Linux - answers2\39
Current kernel: 1.2.13
Oldest kernel: 1.2.3
Used Slackware 3.0.0, rated goodUsed Red Hat 3.0.3, rated goodNumber of Linux servers: 2
Total number of Un*x servers (including Linux): 2
Number of Un*x clients: 0
Number of DOS/Windows clients: 0
Other clients: 0
Average uptime: 30 days
Longest uptime: 63 days
Average E-mail messages/day: 1000
Average http hits/day: 15000
Average FTP Mb/day: 10
WWW server: Apache
Using XFree86Linux information rated fair
Reliability rated good
Robustness rated good
Performance rated good
Hardware support rated good
Software support rated poor
Project support rated poor
Distributor support rated good
News group support rated good
Installation procedures rated fair
Upgrade procedures rated fair
Un*x compatibility rated good
Un*x 'look & feel' rated good
Sharing the network with other Unix OS's rated good
Sharing the network with Windows NT rated good
Sharing the network with Windows95 rated good
Sharing the network with Novell rated fair
Sharing the network with OS/2 rated good
Contact with fellow Linux administrators rated good
Mailing lists: redhat-list@redhat.com
Q: A description of the work in relation to the Linux servers
A: I am the manager of two Red Hat Linux systems serving the customer
needs of PatriotNet, an ISP local to the Fairfax, Virginia area.
Q: A description of the site
A: Our two servers provide standard ISP services: SMTP, HTTP, FTP, DNS,
POP, IMAP, SMB, shell access, INN/NNTP, etc.
Q: What is the most critical aspect of your site?
A: One of our servers provides authentication services for our dial-up
server (a Xylogics Remote Annex 4000). If we lose the authentication
server, our customers can't connect.
Q: What is the history of the site?
A: PatriotNet came on-line last December (1995) with two machines: one
running Slackware 3.0.0 and one running some version of FreeBSD. When
I came on-board in March, I migrated both systems to Red Hat Linux 3.0.3
and we've been using it ever since. Our systems have been stable and
have easily met our needs. The operating system and the kernel have
never been serious problems for us; the most significant problem we
face now is simply hardware limitations.
Q: Why and when did you choose to use Linux?
A: When the company started up, the decision to go with free UNIX was
made for cost reasons. This also keeps us with Red Hat Linux, though
I'd recommend sticking with RHL even if we had the money unless there
was a specific reason to go with another OS (i.e. software not available
for RHL).
Q: Did you experience any failures or hurdles?
A: The most difficulty problems we've faced was moving from Slackware
to Red Hat.
Q: Do you intend to expand the use of Linux at your site, and how?
A: Yes, we are adding new servers to distribute the load. The new servers
will be running either version 3.0.3 or 4.0 of Red Hat Linux.
Q: How do you compare Linux with other Unices you use and have used?
A: I prefer Red Hat Linux over all other flavors of UNIX I've been exposed
to. I've used Digital UNIX, SunOS, and Solaris. I prefer Red Hat Linux
over Slackware.
Q: What commercial software packages do you use with Linux, and are you satisfied?
A: