Re: Help with distributed data access

INFODATA wrote: > > Hi folks, > > I would like some help regarding distributed data access. I have a set-up as > follows: > > A DEC-ALPHA box running I-4GL RDS 6.x and I-Online DS 7.x > > Another NCR box running I-4GL RDS 4.x and I-Online 5.x. > > I have a 4GL application on my ALPHA box that needs to read data from the > Online 5.x server on NCR. I also have I-Star installed on the NCR box. The > communication product for ALPHA is bundled with the engine. > > What would be the environment variables, communication files, etc that I > would have to set up to establish this configuration ? Does my sqlhosts file > on ALPHA have to contain entries for the instance sitting on NCR and vice-versa? Yes, you need to have sqlhosts entries for the NCR server on the ALPHA certainly and it would be good to have the ALPHA defined on the NCR also. Also make sure that the servers are trusted to each other, either totally throught the /etc/hosts.equiv or in the .rhosts for user informix and any other user which will need access to the remote database. BTW those users must exist on both machines, however on the remote machine they do not have to have valid passwords or home directories just an entry in /etc/passwd with a DUMMY passwd and preferably the same user id if possible. Make sure also that the services used in the sqlhosts files for both servers are entered in /etc/services on both machines. If you are accessing the remote database explicitely (ie: mydb@ncr_server) then no special environment variables are needed. To access the database implicitely you either set INFORMIXSERVER=ncr_server on the ALPHA to make the NCR server the default server (in which case you would have to access databases on the local/ALPHA server explicitly) or leave INFORMIXSERVER=alpha_server and export DBPATH=//ncr_server to cause the application to search ncr_server for databases not found locally on the default server ($INFORMIXSERVER). Note that the DBPATH is only used during CONNECT TO and DATABASE statements accesses to remote tables while connected to a local database must name the server explicitely (ie: remote_db@ncr_server:remote_table.some_column). Hope that is enough to get you going. Art S. Kagel