Re: ON-LINe 5.0 -> 6.0

> } > } I am the part-time DBA of two ON-LINE systems on a NCR3450. One is > relatively } complex(JAM and C and ace reports) and one is relatively > simple (ESQL). } > } They are working just fine. > } > } A new system is being planned for this machine and the idea is to > upgrade } to 6.0 for the sake of the new system. > } > } 1) Can ON-LINE 5.0 and 6.0 co-exist on the same machine? > > IMHO: Yes, they can. > > You just make sure that the INFORMIXDIR and TBCONFIG environment > variablesare set properly to point to the appropriate directories and > tbconfig files. Yes, but that's not all there is to it. There are all sorts of other environment variables to take account of; you may also get into trouble about whether or not you're pointing to the right message files. You would also need to change those environment variables to switch from a d/b in the 5.xx instance to one in the 6.xx instance; so distributed queries across the two versions on the same machine becomes a no-no. For example, beware of the setting of the SQLEXEC environment variable. 6.00 uses relay modules (rather than pipes) to communicate between the front-end and the back-end and SQLEXEC needs to be set to point to the correct one. 6.00 also needs you to understand env vars such as DBSERVERNAME and INFORMIXSERVER. You may also end up getting involved in sqlhosts and services files. > > You have to set up different informix directories for each version. Assuming you are running 4.10 front-ends, it may be a good idea to have the 4.10, 5.00 and 6.00 software in three separate directories. But you'll need to have copies of the tbconfig/onconfig and sqlhosts (etc.) files under both the tools and the relevant engine. If you are using 6.00 tools, I doubt very much whether you'll persuade them to talk to 5.xx engines. > > The dbspaces and either the chunks/raw devices must be kept > separate for each engine and version. Yes, and the reason why: 6.00 uses an extra byte on each index to resolve the 'adjacent key lock' issue. Therefore, you can't use the same dbspace for both 5.xx and 6.xx. My advice would be to get an Informix consultant to come and do it for you, or go on one of their upgrade courses. akent@cix.compulink.co.uk (Andy Kent) -------------------------------------