Try the recommended solution for each of the following problems:
If you reboot your cluster, you must restart the Ambari Server and all the Ambari Agents manually.
Charts appear incorrectly or not at all despite Host health status is displayed incorrectly.
SUSE 11 ships with Python version 2.6.0-8.12.2 which contains a known defect that causes this crash.
As an option you can start the HBase REST server manually after the install process is complete. It can be started on any host that has the HBase Master or the Region Server installed. If you install the REST server on the same host as the Ambari server, the http ports will conflict.
On a cluster host ps aux | grep ambari-agent shows more than one agent process running. This causes Ambari Server to get incorrect ids from the host and forces Agent to restart and re-register.
When you start a cluster for the first time, some graphs, such as Services View > HDFS and Services View > MapReduce, do not plot a complete hour of data. Instead, they show data only for the length of time the service has been running. Other graphs display the run of a complete hour.
The Hive Service uses MySQL Server by default. If you choose MySQL server as the database on the Ambari Server host as the managed server for Hive, Ambari stops this database during deployment and crashes.
The cluster fails to install with an error related to running groupmod. This can occur in environments where groups are managed in LDAP, and not on local Linux machines. You may see an error message similar to the following one:
Fail: Execution of 'groupmod hadoop' returned 10. groupmod: group 'hadoop' does not exist in /etc/group
When using SLES and performing host registration using SSH, the Agent bootstrap may fail due to timeout when running the setupAgent.py script. The host on which the timeout occurs will show the following process hanging:
c6401.ambari.apache.org:/etc/ # ps -ef | grep zypper root 18318 18317 5 03:15 pts/1 00:00:00 zypper -q search -s --match-exact ambari-agent
If you have a repository registered that is prompting to accept keys, via user interaction, you may see the hang and timeout. In this case, run
zypper refreshand confirm all repository keys are accepted for the zypper command to work without user interaction.Another alternative is to perform manual Agent setup and not use SSH for host registration. This option does not require that Ambari call zypper without user interaction.
When installing Ambari on RHEL/CentOS 6 using the Cluster Installer Wizard at the Host Checks step, one or more host checks may fail if you have not disabled Transparent Huge Pages on all hosts.
Host Checks will warn you when a failure occurs.
Disable THP. On all hosts,
Add the following command to your
/etc/rc.localfile:if test -f /sys/kernel/mm/transparent_hugepage/enabled; then echo never > /sys/kernel/mm/redhat_transparent_hugepage/enabled fi if test -f /sys/kernel/mm/transparent_hugepage/defrag; then echo never > /sys/kernel/mm/redhat_transparent_hugepage/defrag fiTo confirm, reboot the host then run the following command:
$ cat /sys/kernel/mm/transparent_hugepage/enabled always madvise [never]
