| Bug #54613 | Skipping corrupted tables with ndb_restore | ||
|---|---|---|---|
| Submitted: | 18 Jun 2010 11:05 | Modified: | 13 Dec 2010 2:52 |
| Reporter: | Geert Vanderkelen | Email Updates: | |
| Status: | Closed | Impact on me: | |
| Category: | MySQL Cluster: Cluster (NDB) storage engine | Severity: | S2 (Serious) |
| Version: | mysql-5.1-telco-7.0 | OS: | Any |
| Assigned to: | Jonas Oreland | CPU Architecture: | Any |
[18 Jun 2010 11:18]
Geert Vanderkelen
bzr diff will follow.. when it's done branching..
A diff using MySQL Cluster 7.1.4b:
--- storage/ndb/tools/restore/Restore.cpp 2010-06-18 11:09:01.000000000 +0200
+++ ../mysql-cluster-gpl-7.1.4b/storage/ndb/tools/restore/Restore.cpp 2010-06-09 12:26:00.000000000 +0200
@@ -295,7 +295,7 @@
}
if (!markSysTables())
return 0;
- if (!fixBlobs() && !ga_skip_unknown_objects)
+ if (!fixBlobs())
return 0;
if(!readGCPEntry())
return 0;
[18 Jun 2010 11:40]
Geert Vanderkelen
Dirty patch using an option which is not supposed to be used for this (and a global!)
Attachment: bug54613_dirty.patch (application/octet-stream, text), 424 bytes.
[3 Dec 2010 9:06]
Bugs System
A patch for this bug has been committed. After review, it may be pushed to the relevant source trees for release in the next version. You can access the patch from: http://lists.mysql.com/commits/125899 3359 Jonas Oreland 2010-12-03 ndb - bug#54613 - add new option --skip-broken-object that allows ndb_restore to carry on even if finding corrupt tables in backup file (currently it only handles case with missing blob-tables)
[3 Dec 2010 9:32]
Bugs System
A patch for this bug has been committed. After review, it may be pushed to the relevant source trees for release in the next version. You can access the patch from: http://lists.mysql.com/commits/125904 3359 Jonas Oreland 2010-12-03 ndb - bug#54613 - add new option --skip-broken-object that allows ndb_restore to carry on even if finding corrupt tables in backup file (currently it only handles case with missing blob-tables)
[3 Dec 2010 9:47]
Bugs System
Pushed into mysql-5.1-telco-6.3 5.1.51-ndb-6.3.40 (revid:jonas@mysql.com-20101203092944-gk7c8777qj1gycu0) (version source revid:jonas@mysql.com-20101203092944-gk7c8777qj1gycu0) (merge vers: 5.1.51-ndb-6.3.40) (pib:23)
[3 Dec 2010 9:48]
Bugs System
Pushed into mysql-5.1-telco-7.0 5.1.51-ndb-7.0.21 (revid:jonas@mysql.com-20101203093645-6k4l9nmu50xz7zbv) (version source revid:jonas@mysql.com-20101203093645-6k4l9nmu50xz7zbv) (merge vers: 5.1.51-ndb-7.0.21) (pib:23)
[3 Dec 2010 12:44]
Jonas Oreland
pushed to 6.3.40, 7.0.21 and 7.1.10
[13 Dec 2010 2:52]
Jon Stephens
Documented in the NDB-6.3.40, 7.0.21, and 71.10 changelogs as follows:
Added the --skip-broken-objects option for ndb_restore. This
option causes ndb_restore to ignore tables corrupted due to
missing blob parts tables, and to continue reading from the
backup file and restoring the remaining tables.
Also updated ndb_restore description and related portions of Cluster docs with info about the new option.
Closed.
Description: It should be possible to restore a MySQL Cluster back when a table is, for example, broken because it misses parts table for BLOB-fields. Currently, with MySQL Cluster 6.3 and 7.0 (at least 7.0.14), it is possible that a table is not dropped totally, only the parts tables for the BLOB-fields. This in itself is probably some kind of bug, but it should be possible to exclude this 'broken' table from a backup so we can at least restore the other tables. How to repeat: 13 UserTable Online Yes ham def ndb_t1 3304 TableEvent Online - NDB$BLOBEVENT_REPL$ham/ndb_t1_1 3305 TableEvent Online - NDB$BLOBEVENT_REPL$ham/ndb_t1_2 3306 TableEvent Online - NDB$BLOBEVENT_REPL$ham/ndb_t1_3 The above output of ndb_show_tables (simplified), shows there are BLOBEVENTs, but the parts tables are not there. NDB$BLOB_13_{1,2,3} are missing. To get into this situation, it was necessary to allow ndb_drop_table dropping the parts tables. Changing following 2 functions in storage/ndb/src/ndbapi/NdbDictionaryImpl.cpp to return false instead of true: bool is_ndb_blob_table(const char* name, Uint32* ptab_id, Uint32* pcol_no) { return false; return DictTabInfo::isBlobTableName(name, ptab_id, pcol_no); } bool is_ndb_blob_table(const NdbTableImpl* t) { return false; return is_ndb_blob_table(t->m_internalName.c_str()); } Suggested fix: A every quick but dirty hack is to use the --skip-unknown-objects flag and --exclude-tables options for ndb_restore. The attached patch makes the restore continue, although a message is given: shell> ndb_restore -b 2 -n 2 -m . --skip-unknown-objects --exclude-tables=ham.ndb_t1 .. Table ham/def/ndb_t1 has blob column 1 (c1) with missing parts table in backup. Connected to ndb!! Successfully restored table `ndb_hamspam/def/ndb_t1` Successfully restored table event REPL$ndb_hamspam/ndb_t1 Successfully restored table `test/def/t1` Successfully restored table event REPL$test/t1 Successfully restored table `test/def/ndb_t1` Successfully restored table event REPL$test/ndb_t1 Successfully created index `PRIMARY` on `ndb_t1` Successfully created index `PRIMARY` on `t1` Successfully created index `PRIMARY` on `ndb_t1` It would be much better that --exclude-tables would kick in, but with the source right now, that's a big change, or just way to much extra dev.. Maybe we can add an option --force ..?