Migrating with Enterprise Replication

If you use Enterprise Replication, you must complete replication-related tasks when you migrate to a new version of .

About this task

Prerequisites:

Complete the steps in Preparing for migration.
Complete the steps in Preparing to upgrade with Enterprise Replication
Perform all migration operations as user informix.
All servers in the Enterprise Replication domain must be available, in order for the replication queues to be able to drain.

Procedure

To migrate with Enterprise Replication:

Note:

If you are migrating server from a version lower than 14.10.xC6 to 14.10.xC6 or a later version, after upgrading server to 14.10FC6 or a later version, for the first time when you start ER, make sure to start ER using cdr cleanstart command to force required schema changes to syscdr database.

Starting with 14.10.xC6, send queue spooling of smaller transactions (< ~30kB) will no longer occur to sblobs within sbspaces, but instead go to a new LVARCHAR column within the spool table. As a consequence of this, when spooling occurs, the space consumption might no longer occur mainly in the spool sbspaces (CDR_QDATA_SBSPACE), but rather in the spool table’s dbspace (CDR_QHDR_DBSPACE, defaulting to rootdbs). Having a dedicated, possibly extendable dbspace configured for this purpose is therefor more important now and will take effect with cdr cleanstart.

Perform the tasks that are described in Migrating to the new version of Informix, including starting the new version of the server.
Make sure that no replicable transactions occur before starts.

Especially with the upgrade to version 15.x.x.x from a previous version, the log snooper cannot start snooping at a log position from the previous version’s life, which is one reason why replication should be started for the first time after conversion using cdr cleanstart, directing replication to start snooping at the current log position and meaning that any new transactions prior to this position would not be replicated.

The database server will also demand using cdr cleanstart rather than simple cdr start for the first startup of replication when upgrading from a version prior to 14.10.xC6.
After successful conversion, if you are upgrading server to 14.10xC6 or later version, start by running the cdr cleanstart command, otherwise run cdr start command. All required internal ER conversion now will be performed automatically by the database server.
If you upgraded the servers in a grid from version 11.70 to version 12.10 and you want to copy external files to the servers in the grid, you must enable the ability to copy external files. To enable the copying of external files, run this command:
```
cdr modify grid grid_name --enablegridcopy server_groupname
```

Results

Important: After you convert to the new version of with , do not drop the syscdr database. If you intend to upgrade without replication and re-define it after the upgrade, do the required undefining, including deletion of the replication server definition, prior to the upgrade still in the old version.