More about zombies with SE on Linux

Hi, I've posted this message to both the informix.idn.linux and (accidentally) informix.idn.dynamic4gl news groups, and I'm repeating it here. There's no reason not to use seipcpip with SE on Linux. Nils will probably be updating his HOWTO on the IIUG web site to take this into account -- we may need to get other sources of information fixed too. I'm copying Kurt Wall explicitly since he's looking after an Informix on Linux FAQ. Yours, Jonathan Leffler (jleffler@informix.com) #include <witticism.h> Guardian of DBD::Informix v0.60 -- http://www.perl.com/CPAN Informix IDN for D4GL & Linux -- http://www.informix.com/idn ---------- Forwarded message ---------- Date: Mon, 21 Sep 1998 14:20:50 -0700 From: Jonathan Leffler <jleffler@informix.com> Subject: More about zombies Newsgroups: informix.idn.dynamic4gl Summary: use seipcpip Details: In the SE_7.2 file in $INFORMIXDIR/release/en_us/0333 on the Linux port, it says: 2. The following protocol(s)/interface(s) are supported for this platform: SOCKETS/TCP To use TCP/IP, the nettype field in the sqlhosts file entry must contain "sesoctcp". It never occurred to anybody that this would mislead people into thinking that IPC/PIPE connectivity is not supported. For example, the Solaris 7.24 release notes file only documents TLI using TCP/IP and TLI using IPX/SPX and not IPC/PIPE. I think it is safe to say that there is no Unix or Unix-derived system where Informix-SE runs and seipcpip protocol is not supported. Furthermore, unless you are working with a remote database (on a different machine, or on an NFS-mounted partition), there is no reason to use anything other than seipcpip. However, this omission is exacerbating the problems with zombies; everybody is running sqlexecd because they think they have to. You don't unless people on other computers are trying to access the database. If you have the Linux port, that probably means you should have bought a multi-user licence; the one that comes with the free version is a single-user licence. If you do not use sesoctcp connectivity and therefore do not run sqlexecd, then there is no problem with zombies. Or, put another way: TO AVOID PROBLEMS WITH ZOMBIES, USE SEIPCPIP Caveats about NFS-mounted file systems NFS-mounted file systems cannot be used to host a database. The remote host which has it as a local file system must be running sqlexecd and you should access the database via the network. In traditional versions of Unix, this is enforced by the product; it may or may not be enforced by the Linux version, but expect problems if you try to cheat -- data corruption problems. -- Yours, Jonathan Leffler (jleffler@informix.com) #include Guardian of DBD::Informix v0.60 -- http://www.perl.com/CPAN Informix IDN for D4GL & Linux -- http://www.informix.com/idn PS: Apologies for any weird formatting.