Though there are many good stuff are in Microstrategy KB , yet I believe this should be a good topic to talk about in my blog on "Maintenance Mode Feature in MicroStrategy".
Before Microstrategy release of v9.3.1 , when an Intelligence Server node in a cluster get a normal shut down, the node typically is also removed from the cluster that means anything that is created on that node , for example Cubes or Caches or History messages . while in case of abnormal termination of Intelligence Server process Microstrategy is built smart enough to support high availability seamlessly on a clustered node , that means when abnormal termination takes place , the resource are still available from the other node.
With the release of MicroStrategy 9.3.1 onwards , the Intelligence Server can be configured to keep the Intelligence server clustered resources available seamlessly, even if in the case of node is shutdown normally, this setting can be enabled or disabled from Registry entry , if you are on windows you can configure it under registry & On Linux this can be configured on Linux registry file called MSIReg.reg under installation directory , this setting is called "Maintenance Mode".
Here is step by step instruction to configure this setting on Windows & Linux Implement the steps below to enable maintenance mode. These changes should be implemented on all the nodes of the cluster:
1# Shut down MicroStrategy Intelligence Server(s) where the change needs to be done.
2# Open the Windows registry and navigate to the following location: HKEY_LOCAL_MACHINE\SOFTWARE\MicroStrategy\DSS Server\Castor.
3# Create a new DWORD (32-bit)value and name the entry “MaintenanceModeEnabled” and set its value to 1.The registry location should look as shown in screenshot below.
4# Also, it is recommended for users to create the following two registry entries as well in MicroStrategy Intelligence Server 9.4.1 and later.
These entries should also be created as new DWORD (32-bit) and the value of these entries should be set to 1. SkipClusterChecking Cluster Synch Check Duplicate Cubes ,
The final registry entries should look as shown in the screenshot below: 
Note: To disable maintenance mode, change the value of the newly created registry entry to 0 or delete these entries from the registry. UNIX/Linux Implement the steps below to enable maintenance mode.
These changes should be implemented on all the nodes of the cluster:
1# Stop MicroStrategy Intelligence Server(s) where the change needs to be done.
2# Create a backup of the MSIReg.reg file found in the user's home directory.
3# Edit the MSIReg.reg file, which is found in the MicroStrategy home directory ($MSTR_HOME_PATH).
4# Find the section "HKEY_LOCAL_MACHINE\SOFTWARE\MicroStrategy\DSS Server\Castor".
5# Add the following entries to enable the setting (just below the entry that reads "IgnoreAllExceptions"=dword:00000000: "MaintenanceModeEnabled"=dword:00000001
6# In MicroStrategy Intelligence Server 9.4.1 and later, the following registry entries are also recommended to be added: "SkipClusterChecking"=dword:00000001 "Cluster Synch Check Duplicate Cubes"=dword:00000001
7# Start the Intelligence Server for the change to take effect.
References: Refer to the following MicroStrategy Knowledge Base documents for information on the additional registry settings discussed in the above steps :
TN45399: Maintenance Mode Feature
TN221178: How does the registry setting 'Cluster Synch Check Duplicate Cubes' work in a clustered environment in MicroStrategy 9.4.1 and later
TN47195: In a MicroStrategy 9.2.x - 9.4.x clustered environment, when one of the machines hosting the MicroStrategy Intelligence Servers is shutdown, the performance of other MicroStrategy Intelligence Servers in the cluster is affected.
Thanks for reading.
Regards,
Arun Kumar Gupta
Arun Kumar Gupta
