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This is an automatically generated e-mail. To reply, visit:
https://reviews.apache.org/r/37499/
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Review request for Ambari, Alejandro Fernandez and Nate Cole.
Bugs: AMBARI-12778
https://issues.apache.org/jira/browse/AMBARI-12778
Repository: ambari
Description
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When downgrading a rolling upgrade from HDP 2.3 back to HDP 2.2, all components
will fail with a circular symlink reference.
The problem is that Ambari changes /etc/component/conf from a directory to a
symlink when upgrading to HDP 2.3 from HDP 2.2. During the downgrade, once the
component is put back in HDP 2.2, the following is observed:
```
[root@c6401 flume]# ls -l /etc/flume
total 8
drwxr-xr-x 3 root root 4096 Aug 14 15:44 2.3.2.0-2586
lrwxrwxrwx 1 root root 34 Aug 14 16:14 conf ->
/usr/hdp/current/flume-server/conf
drwxr-xr-x 2 flume root 4096 Aug 14 15:42 conf.backup
(/usr/hdp/2.2.7.0-2816/flume/)
[root@c6401 flume]# ls -l /usr/hdp/current/flume-server/conf
total 16
drwxr-xr-x 2 root root 4096 Aug 14 15:42 bin
lrwxrwxrwx 1 root root 15 Aug 14 15:42 conf -> /etc/flume/conf
drwxr-xr-x 9 root root 4096 Aug 14 15:42 docs
drwxr-xr-x 2 root root 4096 Aug 14 15:42 lib
drwxr-xr-x 2 root root 4096 Aug 14 15:42 tools
```
The solution is to reverse the symlink work done when downgrading from HDP 2.3
back to 2.2.
Diffs
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ambari-common/src/main/python/resource_management/libraries/functions/conf_select.py
a676f74
ambari-server/src/main/resources/common-services/FLUME/1.4.0.2.0/package/scripts/flume_handler.py
a305ce7
ambari-server/src/main/resources/common-services/FLUME/1.4.0.2.0/package/scripts/flume_upgrade.py
7743619
ambari-server/src/main/resources/common-services/FLUME/1.4.0.2.0/package/scripts/params_linux.py
a7efbf6
ambari-server/src/main/resources/custom_actions/scripts/ru_set_all.py f868002
ambari-server/src/main/resources/stacks/HDP/2.2/upgrades/upgrade-2.3.xml
f6823c8
ambari-server/src/test/python/custom_actions/test_ru_set_all.py 211443b
Diff: https://reviews.apache.org/r/37499/diff/
Testing
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Verified fix on a cluster where the problem was reproduced.
mvn clean test
----------------------------------------------------------------------
Total run:789
Total errors:0
Total failures:0
OK
Thanks,
Jonathan Hurley
