Installation guide

2.
Make sure Adaptive Server 15.7 ESD #2 is prepared for downgrade by executing this
command from the master database:
sp_downgrade 'prepare', @toversion='version'
The format for the value of
version does not need periods, so these are all valid:"15.5",
"155", "15.0", "150", "15.0.1", "1501", "15.0.2", "1502", "15.0.3," "1503". The version
you enter should be the Adaptive Server version to which you want to downgrade.
Note: If you have used the 15.0.2 features for encrypted columns and you are downgrading
to:
• Adaptive Server 15.0 or 15.0 ESD #1 – specify the version as "15.0."
• Adaptive Server 15.0, 15.0 ESD #2, 15.0.1, or a 15.0.1 ESD – specify the version as
"15.0.1."
• Adaptive Server 15.0.2 or a 15.0.2 ESD – specify the version as "15.0.2."
sp_downgrade 'prepare' validates the readiness of Adaptive Server 15.7 ESD #2 for
downgrade. It may print messages regarding manual changes required before the
downgrade can be completed. Repeat this step, correcting any errors reported, and make
sure you understand the implications of all warnings before proceeding.
3.
Execute the following, where
version is the same number you used in the previous step:
sp_downgrade 'downgrade', @toversion='version', @override=1
Once this procedure completes successfully, there can be no more activity on the 15.7 ESD
#2 server. Run checkpoint and immediately issue the shutdown command.
Note: Since Adaptive Server 15.7 ESD #2 transaction logs may contain data that older
server versions cannot interpret correctly, all transactions in all databases must be
completed to prevent the older server from recovering any transactions. To ensure that all
transactions are completed, issue the normal shutdown command, and not the shutdown
with nowait command, after running sp_downgrade.
4.
Copy the RUN_SERVER file to the release area for the version you are downgrading to.
Modify the file to use the dataserver binary of the version to which you are downgrading,
using -e, -c, and -M option point to the old server.
For example, if you are downgrading to 15.0.2, change 15.7-related information to 15.0.2-
related information. From the SYBASE directory, issue:
/work_dirs/sybase/ase1502/ASE-15_0/bin/dataserver\
-s old_server_name\
-d downgraded_master_device\
-e old_server_log_file\
-c old_server_config_file\
-M /work_dirs/sybase/ase1502\
5.
Restart the old server using the modified RUN_SERVER file. Ensure that the environment
variable points to the old server release, such as $SYBASE, $SYBASE_ASE, or
$SYBASE_OCS.
Note: When downgrading to a 15.0 or a 15.0.1 server, you can reset user passwords by
setting sp_passwordpolicy 'allow password downgrade' to 0. User passwords are reset
CHAPTER 11: Adaptive Server Downgrades
Installation Guide 107