(Feature available only in Premium Edition. Procedure applicable only for builds prior to PMP 6301. For later versions, refer to click here)
In mission-critical environments, one of the crucial requirements is to provide un-interrupted access to passwords. PMP provides the 'High Availability' feature just to ensure this.
There will be redundant PMP server and database instances
One instance will be the Primary providing read/write access to the users. All users will be connected with primary only
The other instance will act as Secondary
At any point of time data in both Primary and Secondary will be in sync with each other. PMP leverages MySQL's database replication technique for data synchronization. The data replication happens through a secure, encrypted channel
When Primary server goes down, the Secondary will offer 'Read Only' access to the users, until the fully-functional primary server is brought back to service. The changes made in the database in the intervening period will be automatically synchronized upon connection restoration
Scenario 1 - Primary & Secondary in different geographical locations and WAN Link failure happens between the locations
Assume that the Primary Server is in one geographical location 'A' and Secondary is deployed in another location 'B'. The users in both the locations will be connected to the Primary and will be carrying out password management activities. At any point of time data in both Primary and Secondary will be sync with each other. Assume there happens loss of network connectivity between the two locations. In such a scenario, users in location 'A' will continue to remain connected with the primary and will be doing all operations. Users in location 'B' will be able to get emergency read-only access to the passwords from Secondary. Once the network between the two locations is up again, data in both the locations will be synchronized.
Scenario 2 - Primary & Secondary within the same network & Primary goes down
In
case, the Primary crashes or goes down, the users in location 'A' &
'B' can rely upon the emergency read-only access to the passwords from
the Secondary.
What happens to Audit Trails?
In the high availability scenarios mentioned above, audit trails will be recorded as usual. In scenario 1, as long as there is network connectivity between the two locations, the audit trails will be printed by the primary. When users connect to the Secondary, it will print operations such as 'password retrieval', 'login' and 'logout'. When the two locations get back network connectivity, the audit data will be synchronized. In scenario 2, when the primary crashes, the 'password retrieval', 'login' and 'logout' done by the users in secondary will be audited. Other audit records will already be in sync at the Standby.
Setting up high availability in PMP consists
of the following four steps:
1. Installing Primary & Secondary instances (you can use your existing installation as Primary and install another PMP instance as standby in a separate work station)
2. Configurations to be done in Primary Installation
3. Configurations to be done in Secondary Installation
4. Enabling database replication
Carry out the steps on-by-one as detailed below.
|
Step 1 Primary & Secondary Setup
Important Note:
If you delete them, you will lose all your data. |
Step 2 - Configurations to be done in Primary Installation
Prerequisite
Stop PMP Primary server, if already running
Check if PMP Secondary Server is reachable from Primary Server and vice-versa (do a ping)
Go to the PMP Primary
folders and carry out the following:
Navigate to <PMP_Installation_Folder>/mysql/data
folder. The following
file & folders are important:
'passtrix' folder,
server-key.pem
KEEP THESE FOLDERS and delete all other files.
Steps
Open a command prompt and navigate to <PMP_Installation_Folder>/bin directory and run the script replicationPack.bat (Windows)/ replicationPack.sh (Linux)
This will create a replication package named 'Replication.zip' under <PMP_Home>/replication folder. This zip contains the database package for standby
Go to <PMP_Installation_Folder>/mysql/bin directory. You will find a file named HAPrimary.conf, rename that file as HASecondary.conf. Important Note: Before proceeding further, ensure that HAPrimary.conf is NOT present under PMP_Installation_Folder>/mysql/bin folder. It should only contain HASecondary.conf
Edit the HASecondary.conf
and enter the following details:
Enter the name of the host where the secondary server is running:
master_host=<hostname of Secondary>
For example, 'test_workstation' is the machine where the secondary
PMP server is running, you need to enter the information as below:
master_host=test_workstation
Enter the host name, DNS Name and IP address of the secondary server:
slave_hosts=<hostname of Secondary>,<DNS Name of Secondary>,<IP
of Secondary>
For example, 'test_workstation' is the machine where the secondary
PMP server is running, test_workstation.test.com is the DNS name and 192.168.10.1
is its IP, you need to enter the information as below (in comma separated
form without any space):
slave_hosts=test_workstation,test_workstation.test.com,192.168.10.1
Open a command prompt and navigate to <PMP_Installation_Folder>/bin
and run the script startDB.bat <MySQL
Port> (Windows) / startDB.sh
<MySQL Port> (Linux). You need to provide the MySQL port
of PMP while executing the above script as shown below. By default, the
MySQL port in PMP is 2345.
startDB.bat <MySQL Port> (For Windows)
startDB.sh <MySQL Port> (For Linux)
For example, with the default the MySQL port 2345, you need to execute
this as:
startDB.bat 2345 (For Windows)
startDB.sh 2345 (For Linux)
This will start the Primary Database (Default MySQL port is 2345)
Copy the Replication.zip file present under <PMP_Installation_Folder>/replication directory. This has to be put in the PMP Secondary installation machine as detailed in Step 3 below.
Step 3 - Changes in Secondary Installation
Prerequisite
Stop PMP Secondary server, if already running
Check if PMP Primary Server is reachable from Secondary Server and vice-versa (do a ping)
Go to the PMP Secondary
folder and carry out the following:
Navigate to <PMP_Installation_Folder>/mysql/data
folder. The following
file & folders are important:
'passtrix' folder,
server-key.pem
KEEP THESE FOLDERS and delete all other files.
Steps
Put the Replication.zip file copied from the PRIMARY Installation (as detailed in the previous step) in to the <PMP_Installation_Folder> of Secondary and unzip it. Take care to extract the files under <PMP_Installation_Folder> only. It will overwrite the existing data files.
Copy the <PMP_Installation_Folder>/mysql/bin/database_params.conf file of secondary installation and put it over <PMP_Installation_Folder>/conf directory of secondary installation
Go to <PMP_Installation_Folder>/mysql/bin directory. You will find a file named HAPrimary.conf. Important Note: Before proceeding further, ensure that HASecondary.conf is NOT present under PMP_Installation_Folder>/mysql/bin folder. It should only contain HAPrimary.conf
Edit the HAPrimary.conf
and enter the following details:
Enter the name of the host where the primary server is running:
master_host=<hostname of Primary>
For example, 'test_workstation' is the machine where the primary PMP
server is running, you need to enter the information as below:
master_host=test_workstation
Enter the host name, DNS Name and IP address of the primary server:
slave_hosts=<hostname of Primary>,<DNS Name of Primary>,<IP
of Primary>
For example, 'test_workstation' is the machine where the primary PMP
server is running, test_workstation.test.com is the DNS name and 192.168.10.1
is its IP, you need to enter the information as below:
slave_hosts=test_workstation,test_workstation.test.com,192.168.10.1
Copy the startDB.bat (in Windows) / startDB.sh (in Linux) file present under <PMP_Installation_Folder>/mysql/bin of secondary installation and put it over <PMP_Installation_Folder>/bin directory of secondary installation
Go to <PMP_Installation_Folder>/bin
of secondary installation and execute startDB.bat
<MySQL Port> (in Windows) / startDB.sh
<MySQL Port>
(in Linux) to start Secondary database (Default MySQL port is 2345)
For example, with the default the MySQL port 2345, you need to execute
this as:
startDB.bat 2345 (For Windows)
startDB.sh 2345 (For Linux)
This will start the Secondary Database (Default
MySQL port is 2345)
Step 4 - Enabling Database Replication - This is to be done in both Primary and Secondary Installations
Run enableReplication.bat (in Windows) / enableReplication.sh (in Linux) present in <PMP_Installation_Folder>/mysql/bin of both Primary and Secondary installations
Step 4 - Start Primary and Secondary
Navigate to PMP Primary server installation and terminate the PMP's mysqld process and start PMP service
Similarly, navigate to the PMP Secondary installation and terminate the corresponding mysqld process and start PMP service on Secondary
High Availability setup is now ready
After carrying out the above steps, you can verify if the High Availability setup is working properly by looking at the message in "Admin >> General >> High Availability" page of Primary server. If the setup is proper, you will see the following:
High Availability Status: Alive
Replication Status: Alive
If both the above messages show "Alive", it indicates that high availability is working fine. In case, if the status turns 'Failed', it indicates failure of the setup.
What does 'High Availability Status' Indicate (Alive/Failed)?
Constant replication of data between Primary and Standby server is the technology underlying high availability. The status 'Alive' indicates perfect data replication and data synchronization. If there happens any disruption like network problems between Primary and Standby (in turn between the databases), the status will get changed to 'Failed'.
This may happen when there is no communication/connection between the database of primary server and that of the standby server. When the connection gets reestablished, data synchronization will happen and both databases will be in sync with each other. During the intervening period, those who have connected to the primary and standby will not face any disruption in service.
In short, this status is only an indication of the connection/communication between databases and does not warrant any troubleshooting.
What does 'Replication Status' Indicate (Alive/Failed)?
As mentioned above, high availability leverages the MySQL replication feature. The database of Primary server acts as the Master and the one with Standby acts as the 'Slave'. When the data gets replicated properly, the status will be 'Alive'. In case, there happens any error in updating the data or query failure, the replication status become 'Failed'.
Once the status becomes failed, PMP High Availability setup also breaks down. That means, you will have to configure high availability setup all over again.
If you find the status marked as 'Failed' even after re-configuring High Availability, you may have to contact PMP support with the following log files:
PMP In Windows: <PMP Installation Folder>/mysql/data/<hostname>.err file
PMP In Linux: <PMP Installation Folder>/mysql/data/tmp/ .out file
Alerting Mechanism for Status Failure
Since the above two conditions assume importance in high availability setup, it is important to receive real-time alerts when the status turns Alive to Failed and vice-versa. To configure alerts, go to Audit >> Resource Audit >> Configure User Audit >> General Operations and select the mode of alert (email/SNMP trap/Syslog message) for the events 'High Availability Alive' and 'High Availability Failed'.
Note 1 : In case, the Primary Server crashes, when carrying out disaster recovery, please ensure the following:
Go to the <PMP_Home>/mysql/data of secondary server and copy the files ibdata1, passtrix
Install another instance of PMP afresh (same version as that of the PMP secondary from which you copied the above files)
In the new installation, go to <PMP_Home>/mysql/data and overwrite the ibdata1, passtrix files
Start the new PMP installation
Note 2:
After configuring high availability, if you change
the port of the Primary PMP server, the high availability setup will not
work. It has to be re-configured with suitable changes.
Note 3:
If you have configured TFA
Refer to the 'Troubleshooting Tips' section in the High Availability Tutorial.
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