Informix SE over NFS???
Christian wanted a second machine to run Informix SE 7.24 against .dat/.idx files held on another box, but SE refuses NFS-mounted data (C-ISAM error) and he hoped to avoid INFORMIX-NET. Replies said client/server via the sqlexecd listener is the only supported route. His real goal was to offload SQL work from an overloaded box also running a C-ISAM ERP app. Art Kagel suggested reversing the setup: put the files on the new Linux/Informix server and NFS-mount them to the old box for C-ISAM access (C-ISAM tolerates NFS), ideally recoding the C-ISAM app to SQL. Walt Hultgren cautioned that NFS access by the database would shift heavy traffic onto the network and could hurt performance. No outcome reported.
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Hello, we want to access to INFORMIX-SE-tables (V.7.24) from the DB-server to another server, where the physical tables (.dat, .idx) are stored. if we use access via NFS we got a C-ISAM-Error (->can't use nfs). is there any other possibility to have access directly to the tables (not using INFORMIX-NET!). Christian
Christian Schulz <Ch.Schulz@hubner-germany.com> wrote: > Hello, > we want to access to INFORMIX-SE-tables (V.7.24) from the > DB-server to another server, where the physical > tables (.dat, .idx) are stored. > if we use access via NFS we got a > C-ISAM-Error (->can't use nfs). is there any other > possibility to have access directly to the tables > (not using INFORMIX-NET!). > With that version of SE I believe that will have sqlexecd which will allow remote access. /J\\ -- "The Tory Party is like a wonky shopping trolley - it pulls to the left, it pulls to the right, but you just can't get it to go forward" - John Prescott
> Hello, > we want to access to INFORMIX-SE-tables (V.7.24) from the > DB-server to another server, where the physical > tables (.dat, .idx) are stored. > if we use access via NFS we got a > C-ISAM-Error (->can't use nfs). is there any other > possibility to have access directly to the tables > (not using INFORMIX-NET!). > > Christian > If you have the Informix binaries on both machines, you might try either creating a synonym (create synonym <sometable> for <sometable@someserver>) or creating a view with the same name as the remote table. -- # unrm / ksh: unrm: not found # man cpio Sent via Deja.com http://www.deja.com/ Before you buy.
INET is the only way. You would run a listener on the machine that owns the disks (that is sqlexecd) and clients apps on the other machine connect over TCP/IP. This is simple and fast. What are your problems with doing things this way? Art S. Kagel Christian Schulz wrote: > Hello, > we want to access to INFORMIX-SE-tables (V.7.24) from the > DB-server to another server, where the physical > tables (.dat, .idx) are stored. > if we use access via NFS we got a > C-ISAM-Error (->can't use nfs). is there any other > possibility to have access directly to the tables > (not using INFORMIX-NET!). > > Christian
On Wed, 26 Jan 2000 15:08:29 -0500, "Art S. Kagel" <kagel@bloomberg.net> wrote: >INET is the only way. You would run a listener on the machine that owns >the disks >(that is sqlexecd) and clients apps on the other machine connect over >TCP/IP. This >is simple and fast. What are your problems with doing things this way? > >Art S. Kagel you asked what our problem is: there are two apps which use the original files on the machine, a erp-system (with CISAM-access) and SQL-statements with access via client-ODBC and Informix. but the processes from both sides kill the machines performance. therefore we want to separate the informix-processes from this box1 by putting it on a new linux-server (upgrading the hardware from box1 is too expensive)! and now we need access to the original files on the first machine. Christian
Christian Schulz wrote: > On Wed, 26 Jan 2000 15:08:29 -0500, "Art S. Kagel" > <kagel@bloomberg.net> wrote: > > >INET is the only way. You would run a listener on the machine that owns > >the disks > >(that is sqlexecd) and clients apps on the other machine connect over > >TCP/IP. This > >is simple and fast. What are your problems with doing things this way? > > > >Art S. Kagel > > you asked what our problem is: > > there are two apps which use the original files on the > machine, a erp-system (with CISAM-access) and SQL-statements > with access via client-ODBC and Informix. but the processes > from both sides kill the machines performance. > therefore we want to separate the informix-processes > from this box1 by putting it on a new linux-server > (upgrading the hardware from box1 is too expensive)! > and now we need access to the original files on > the first machine. Hey, if I know the problem I can suggest a solution. Put the files on the machine that will be running the Informix and NFS mount the files to the other machine for CISAM access since CISAM does not mind NFS mounted files. You just have to reverse your outlook. In the long run may I suggest you recode the CISAM stuff to use SQL access so you can be independent of such problems, perhaps even be able to migrate the apps to IDS if needed in the future. Art S. Kagel
Christian Schulz wrote: > > On Wed, 26 Jan 2000 15:08:29 -0500, "Art S. Kagel" > <kagel@bloomberg.net> wrote: > > >INET is the only way. > >[...] > >Art S. Kagel > > [...] > therefore we want to separate the informix-processes > from this box1 by putting it on a new linux-server Back when Informix didn't allow SE access across NFS, the implied reason in the doc's was to keep users from hurting themselves. While I was a bit suspicious of that being the only reason, it was a good point. To wit: If you make a client/server connection between the two systems, only SQL goes from c->s and only the results go from s->c. However, if server2 gets at the *.dat and *.idx files on server1 via NFS, server1 must transfer lots of stuff over the network as server2 paws through whatever files it needs to read, including any portions of the files it needs to skip, to find the results it returns to the requesting client. So, you may find that setting up Informix on a second server but forcing it to get at the constituent files of the database via NFS may in fact give you a net loss in performance depending on your app. I don't know how I would go about doing some pre-testing or prototyping of this short of actually installing everything. Maybe you could start the process you plan to leave on server1 and simultaneously do a lot of NFS I/O from server2 and see what that does to performance. All of the above is semi-theoretical, since I never went past the investigation stage on a similar project. If you actually set things up this way, I'd like to hear how well it works for you. Good luck, Walt. -- Walt Hultgren Manager, Information Technology Yerkes Research Center of Emory University Mailto:walt@rmy.emory.edu -- 404-727-0648