Red Hat Bugzilla – Bug 470576
Migration could do addition checks before commiting actions
Last modified: 2016-05-06 10:29:01 EDT
Description of problem: During migration, there are a number of error conditions that will cause migration to fail. Since migration attempts to perform its steps in an atomic-like operation, users must remove bogus instances and configuration in order to recover and attempt to re-migrate. There are several steps that migration could perform before starting to create new server instances: - Handle SSL (migration will fail if SSL is on and no pin file exists or the certificate is expired) - Validate schema (server may fail to start up if new schema conflicts with already installed schema, such as the Samba password policy schema). - Verify that LDIF files of the data bases exists, if migration requires them. - Verify sufficient disk space to complete new instance import.
I think that the schema check may be difficult to do without creating the new instance first, but the rest of the requested checks should be implemented without too much difficulty. For the schema validation, it's best to leverage the schema validation code that the ns-slapd program already does. The best way of doing this is to create the new instance (with new default schema), then try to migrate in the schema from the old instance. If we don't create a new instance first, we would need to have full schema parsing and validation logic in the migration code.
It turns out that most of these checks will require more work than anticipated. The best approach would really be to make migration clean up after itself in the case of a failure. This approach would not make us try to check difficult things such as the result of schema merging in the migration Perl code. Pushing this to 8.2.
Created attachment 455211 [details] 0001-Bug-470576-ds.patch
Created attachment 455212 [details] 0001-Bug-470576-admin.patch
Created attachment 473385 [details] Revised Patch This simply removes an unnecessary for loop from the previous ds patch.
Pushed revised DS patch to master. Counting objects: 13, done. Delta compression using up to 2 threads. Compressing objects: 100% (6/6), done. Writing objects: 100% (7/7), 994 bytes, done. Total 7 (delta 5), reused 0 (delta 0) To ssh://git.fedorahosted.org/git/389/ds.git 3bcba24..8aee2bd master -> master
Pushed admin patch to master. Counting objects: 19, done. Delta compression using up to 2 threads. Compressing objects: 100% (9/9), done. Writing objects: 100% (10/10), 1.93 KiB, done. Total 10 (delta 8), reused 0 (delta 0) To ssh://git.fedorahosted.org/git/389/admin.git 3be5637..cbd46e4 master -> master