How the Evidian SafeKit software simply implements a Hanwha Wisenet SSM high availability cluster?
The solution for Hanwha Wisenet SSM
Evidian SafeKit brings high availability to Hanwha Wisenet SSM, the CCTV video surveillance system, between two redundant servers.
This article explains how to implement quickly a Hanwha cluster with real-time replication and automatic failover of Wisenet SSM services and data.
A free trial and the Hanwha high availability module are offered in this article.
An alternative solution
There is another SafeKit solution very easy to deploy and based on Hyper-V if you need to replicate other applications in addition to Hanwha Wisenet SSM.
The SafeKit/Hyper-V solution replicates full Hyper-V virtual machines which can contain Hanwha Wisenet SSM and other applications. And SafeKit restarts automatically the VMs in case of failure.
Several virtual machines can be replicated and can run on both Windows hypervisors with crossed replication and mutual takeover.
With this solution, there is no need to configure restart scripts and define virtual IP addresses for each application.
A generic product
Note that SafeKit is a generic product on Windows and Linux.
You can implement with the same product real-time replication and failover of any file directory and service, database, complete Hyper-V or KVM virtual machines, Docker, Kubernetes , Cloud applications.
SafeKit: an ideal solution for a partner application
This platform agnostic solution is ideal for a partner with a critical application and who wants to provide a high availability option easy to deploy to many customers.
This clustering solution is also recognized as the simplest to implement by our partners.
How the SafeKit mirror cluster works with Hanwha Wisenet SSM?
Step 1. Real-time replication
Server 1 (PRIM) runs the Hanwha Wisenet SSM application. Clients are connected to a virtual IP address. SafeKit replicates in real time modifications made inside files through the network.
The replication is synchronous with no data loss on failure contrary to asynchronous replication.
You just have to configure the names of directories to replicate in SafeKit. There are no pre-requisites on disk organization. Directories may be located in the system disk.
Step 2. Automatic failover
When Server 1 fails, Server 2 takes over. SafeKit switches the virtual IP address and restarts the Hanwha Wisenet SSM application automatically on Server 2.
The application finds the files replicated by SafeKit uptodate on Server 2. The application continues to run on Server 2 by locally modifying its files that are no longer replicated to Server 1.
The failover time is equal to the fault-detection time (30 seconds by default) plus the application start-up time.
Step 3. Automatic failback
Failback involves restarting Server 1 after fixing the problem that caused it to fail.
SafeKit automatically resynchronizes the files, updating only the files modified on Server 2 while Server 1 was halted.
Failback takes place without disturbing the Hanwha Wisenet SSM application, which can continue running on Server 2.
Step 4. Back to normal
After reintegration, the files are once again in mirror mode, as in step 1. The system is back in high-availability mode, with the Hanwha Wisenet SSM application running on Server 2 and SafeKit replicating file updates to Server 1.
If the administrator wishes the application to run on Server 1, he/she can execute a "swap" command either manually at an appropriate time, or automatically through configuration.
Choose between high availability at the application level or at the virtual machine level
High availability at the application level
In this type of solution, only application data are replicated. And only the application is restared in case of failure. Restart scripts must be written to restart the application. This solution is platform agnostic and works with physical machines, virtual machines, in the Cloud.
We deliver application modules to implement this type of solution (like the Hanwha Wisenet SSM module provided in the free trial below). They are preconfigured for well known applications and databases. You can customize them with your own services, data to replicate, application checkers. And you can combine application modules to build advanced multi-level architectures.
High availability at the virtual machine level
In this type of solution, the full Virtual Machine (VM) is replicated (Application + OS). And the full VM is restarted in case of failure. The advantage is that there is no restart scripts to write per application and no virtual IP address to define. If you do not know how the application works, this is the best solution.
We deliver two modules for implementing this solution: one for Hyper-V on Windows and one for KVM on Linux. Several VMs can be replicated and can run on both hypervisors with crossed replication and mutual takeover.
Use backup solutions with asynchronous replication for high latency network.
Evidian SafeKit free trial + module for Hanwha Wisenet SSM
SafeKit free trial + module for Hanwha Wisenet SSM
Prerequisites
You need Wisenet SSM installed on 2 nodes (virtual machines or physical servers).
On Windows, with Windows services manager, put Wisenet SSM services with Boot Startup Type = Manual on both nodes.
SafeKit controls start of Wisenet SSM services in the restart scripts. Edit the restart scripts during the configuration to check if you have put all services in Manual boot including the new ones that you can add.
Install the free version of SafeKit on 2 Windows nodes.
Note: the free trial includes all SafeKit features. At the end of the trial, you can activate permanent license keys without uninstalling the package.
To open the Windows firewall, on both nodes start a command line as administrator, goto C:\safekit\private\bin and type .\firewallcfg.cmd add.
For synchronizing SafeKit at boot and at shutdown, on both nodes start a command line as administrator, goto C:\safekit\private\bin and type .\addStartupShutdown.cmd only once.
Then, click on the red floppy disk to save the configuration.
If node1 or node2 background color is red, check connectivity of the browser to both nodes and check firewall on both nodes for troubleshooting.
This operation will place the IP addresses in the cluster.xml file on both nodes (more information in the training with the command line).
Step 3. Choose the module
In the Configuration tab, click on the hanwha_ssm.safe module.
The console finds xxx.safe in the 'Application_Modules/demo/' directory on the server side if you dropped a module there during installation.
Step 4. Configure the module
Check that the replicated directories are installed on both nodes and contain the application data.
Replication of data and also logs is required for a database.
You can add new replicated directories as needed.
Enter a virtual IP address. A virtual IP address is a standard IP address in the same IP network (same subnet) as the IP addresses of both nodes.
Application clients must be configured with the virtual IP address (or the DNS name associated with the virtual IP address).
The virtual IP address is automatically switched in the event of a failure.
start_prim and stop_prim must contain starting and stopping of the Wisenet SSM application.
You can add new services in these scripts.
Check that the names of the services in these scripts are those installed on both nodes, otherwise modify them in the scripts.
Stop the services configured in start_prim on both nodes.
On Windows and on both nodes, with the Windows services manager, set Boot Startup Type = Manual for all the services registered in start_prim (SafeKit controls the start of services in start_prim).
Note that if a process name is displayed in Process Checker, it will be monitored with a restart action in case of failure. Configuring a wrong process name will cause the module to stop right after its start.
This operation will report the configuration in the userconfig.xml, start_prim, stop_prim files on both nodes (more information in the training with the command line).
Step 5. Verify successful configuration
Check the success message (green) on both nodes and click Next.
If node 1 has up-to-date replicated directories, select it and start it.
When node 2 will be started, all data from node 1 will be copied to node 2.
If you make the wrong choice, you run the risk of synchronizing outdated data on both nodes.
It is also assumed that the services modifying the replicated directories are stopped in order to be able to install the replication mechanisms and then start the Wisenet SSM application in start_prim.
Step 7. Wait for the transition to ALONE (green)
Node 1 should reach the ALONE (green) state, which means that the start_prim script has been executed on node 1.
If the status is ALONE (green) and the Wisenet SSM application is not started, check output messages of the start_prim script in the Application Log on node 1.
If node 1 does not reach ALONE (green) state, analyze why with the Module Log of node 1.
If the cluster is in [WAIT (red) not uptodate - STOP (red) not uptodate] state, stop the WAIT node and force its start as primary.
Step 8. Start node 2
Start node 2 with its contextual menu.
Node 2 should go to SECOND green after resynchronizing all replicated directories (binary copy from node 1 to node 2).
This may take a while depending on the size of replicated directories and the network bandwidth.
If node 2 does not reach SECOND (green) state, analyze why with the Module Log of node 2.
Step 9. Verify that the cluster is operational
The cluster is up with Wisenet SSM services running on the PRIM node and not running on the SECOND node. Only changes inside files are replicated in real time in this state.
Warning, components that are clients of Wisenet SSM services must be configured with the virtual IP address. The configuration can be done with a DNS name (if a DNS name has been created and associated with the virtual IP address).
Step 10. Automatically start the module at boot
'Configure boot start' configures the automatic start of the module at boot.
Do this configuration on node 1 as shown in the figure, once the high availability solution is working properly.
And redo this same configuration on node 2.
Step 11. Testing
Stop the PRIM node by scrolling down its contextual menu and clicking Stop. Verify that there is a failover on the SECOND node which should become ALONE (green).
And with Microsoft Management Console (MMC) on Windows or with command lines on Linux, check the failover of Wisenet SSM services (stopped on node 1 in the stop_prim script and started on node 2 in the start_prim script).
If the Wisenet SSM application is not started on node 2 while the state is ALONE (green), check output messages of the start_prim script in the Application Log of node 2.
If ALONE (green) is not reached, analyze why with the Module Log of node 2.
In Advanced Configuration tab, you can edit internal files of the module: bin/start_prim and bin/stop_prim and conf/userconfig.xml .
If you make change in the internal files here, you must apply the new configuration by a right click on the icon/xxx on the left side (see image): the interface will allow you to redeploy the modified files on both servers.
<!DOCTYPE safe>
<safe>
<service mode="mirror" defaultprim="alone" maxloop="3" loop_interval="24" failover="on">
<!-- Heartbeat Configuration -->
<!-- Names or IP addresses on the default network are set during initialization in the console -->
<heart pulse="700" timeout="30000">
<heartbeat name="default" ident="flow">
</heartbeat>
</heart>
<!-- Virtual IP Configuration -->
<!-- Replace
* VIRTUAL_TO_BE_DEFINED by the name of your virtual server
-->
<vip>
<interface_list>
<interface check="on" arpreroute="on">
<real_interface>
<virtual_addr addr="VIRTUAL_TO_BE_DEFINED" where="one_side_alias" />
</real_interface>
</interface>
</interface_list>
</vip>
<!-- Software Error Detection Configuration -->
<errd polltimer="10">
<!-- Samsung SSM process -->
<proc name="pg_ctl.exe" atleast="1" action="restart" class="prim" />
<proc name="ServiceManager.exe" atleast="1" action="restart" class="prim" />
<!--
<proc name="HAServerService.exe" atleast="1" action="restart" class="prim"/>
-->
</errd>
<!-- File Replication Configuration -->
<!-- Adapt with the directory of your PostgreSQL database and logs
-->
<rfs async="second" acl="off" nbrei="3">
<replicated dir="C:\PostgreSQL\9.1\data" mode="read_only">
<notreplicated path="pg_log"/>
<notreplicated path="postmaster.pid"/>
</replicated>
<replicated dir="C:\Program Files (x86)\Samsung\SSM\SystemManager\MapFile" mode="read_only"/>
</rfs>
<!-- User scripts activation -->
<user nicestoptimeout="300" forcestoptimeout="300" logging="userlog" />
</service>
</safe>
start_prim.cmd
@echo off
rem Script called on the primary server for starting application services
rem For logging into SafeKit log use:
rem "%SAFE%\safekit" printi | printe "message"
rem stdout goes into Application log
echo "Running start_prim %*"
set res=0
rem TODO: set to manual the start of services when the system boots
net start "postgresql-9.1 - PostgreSQL Server 9.1"
if not %errorlevel% == 0 (
%SAFE%\safekit printi "PostgreSQL (postgresql-9.1 - PostgreSQL Server 9.1) start failed"
goto stop
) else (
%SAFE%\safekit printi "PostgreSQL (postgresql-9.1 - PostgreSQL Server 9.1) started"
)
net start "SSM System Manager"
if not %errorlevel% == 0 (
%SAFE%\safekit printi "SSM System Manager start failed")
goto stop
) else (
%SAFE%\safekit printi "SSM System Manager started"
)
net start "SSM Watch Services Manager"
if not %errorlevel% == 0 (
%SAFE%\safekit printi "SSM Watch Services Manager start failed"
goto stop
) else (
%SAFE%\safekit printi "SSM Watch Services Manager started"
)
rem net start "HA Server Service"
rem if not %errorlevel% == 0 (
rem %SAFE%\safekit printi "HA Server Service start failed"
rem goto stop
rem ) else (
rem %SAFE%\safekit printi "HA Server Service started"
rem )
if %res% == 0 goto end
:stop
set res=%errorlevel%
"%SAFE%\safekit" printe "start_prim failed"
rem uncomment to stop SafeKit when critical
rem "%SAFE%\safekit" stop -i "start_prim"
:end
stop_prim.cmd
@echo off
rem Script called on the primary server for stopping application services
rem For logging into SafeKit log use:
rem "%SAFE%\safekit" printi | printe "message"
rem ----------------------------------------------------------
rem
rem 2 stop modes:
rem
rem - graceful stop
rem call standard application stop with net stop
rem
rem - force stop (%1=force)
rem kill application's processes
rem
rem ----------------------------------------------------------
rem stdout goes into Application log
echo "Running stop_prim %*"
set res=0
rem action on force stop
if "%1" == "force" (
%SAFE%\safekit printi "Force stop: kill processes of Samsung SSM application"
%SAFE%\safekit kill -name="watchservices.exe" -level="terminate"
%SAFE%\safekit kill -name="java.exe" -argregex=".*systemmanager.*" -level="terminate"
%SAFE%\safekit kill -name="pg_ctl.exe" -level="terminate"
%SAFE%\safekit kill -name="postgres.exe" -level="terminate"
%SAFE%\safekit kill -name="HAServerService.exe" -level="terminate"
%SAFE%\safekit kill -name="systemanager.exe" -level="terminate"
goto end
)
rem %SAFE%\safekit printi "Stopping HA Server Service"
rem net stop "HA Server Service"
%SAFE%\safekit printi "Stopping SSM Watch Services Manager"
net stop "SSM Watch Services Manager"
%SAFE%\safekit printi "Stopping SSM System Manager"
net stop "SSM System Manager"
%SAFE%\safekit printi "Stopping PostgreSQL (postgresql-9.1 - PostgreSQL Server 9.1)"
net stop "postgresql-9.1 - PostgreSQL Server 9.1"
del C:\PostgreSQL\9.1\data\postmaster.pid
rem Wait a little for the real stop of services
"%SAFEBIN%\sleep" 10
if %res% == 0 goto end
"%SAFE%\safekit" printe "stop_prim failed"
:end
SafeKit Modules for Plug&Play High Availability Solutions
“Noemis, a value added distributor of Milestone Video Surveillance, has assisted integrators to deploy the SafeKit redundancy solution on many projects such as city surveillance, datacenters, stadiums and other critical infrastructures. SafeKit is a great product, and Evidian provides a great support.”
Sebastien Temoin, Technical and Innovation Director, NOEMIS, value added distributor of Milestone solutions:
"SafeKit by Evidian is a professional solution making easy the redundancy of Milestone Management Server, Event Server, Log Server. The solution is easy to deploy, easy to maintain and can be added on existing installation. We have assisted integrators to deploy the solution on many projects such as city surveillance, datacenters, stadiums and other critical infrastructures. SafeKit is a great product, and Evidian provides great support. Happy to help if you have any questions."
Harmonic is using SafeKit as a software OEM high availability solution and deploys it with its TV broadcasting solutions over satellites, terrestrials, cable, IPTV.
“SafeKit is the ideal application clustering solution for a software publisher looking for a simple and economical high availability software. We are deploying SafeKit worldwide and we currently have more than 80 SafeKit clusters on Windows with our critical TV broadcasting application through terrestrial, satellite, cable and IP-TV. SafeKit implements the continuous and real-time replication of our database as well as the automatic failover of our application for software and hardware failures. Without modifying our application, it was possible for us to customize the installation of SafeKit. Since then, the time of preparation and implementation has been significantly reduced.”
Finance [+]
The European Society of Warranties and Guarantees in Natixis uses SafeKit as a high availability solution for its applications.
Over 30 SafeKit clusters are deployed on Unix and Windows in Natixis.
Over 20 SafeKit clusters are deployed on Linux and Windows with Oracle.
Testimonial of Fives Syleps:
"The automated factories that we equip rely on our ERP. It is not possible that our ERP is out of service due to a computer failure. Otherwise, the whole activity of the factory stops.
We chose the Evidian SafeKit high availability product because it is an easy to use solution. It is implemented on standard servers and does not require the use of shared disks on a SAN and load balancing network boxes.
It allows servers to be put in remote computer rooms. In addition, the solution is homogeneous for Linux and Windows platforms. And it provides 3 functionalities: load balancing between servers, automatic failover and real-time data replication.”
Tony Myers, Director of Business Development says:
"By developing applications for air traffic control, Copperchase is in one of the most critical business activities. We absolutely need our applications to be available all the time. We have found with SafeKit a simple and complete clustering solution for our needs. This software combines in a single product load balancing, real time data replication with no data loss and automatic failover. This is why, Copperchase deploys SafeKit for air traffic control in airports in the UK and the 30 countries where we are present."
Over 25 SafeKit clusters are deployed on Linux with Oracle.
Peter Knight, Sales Manager says:
"Business continuity and disaster recovery are a major concern for our Locus banking application deployed in numerous Credit Unions around Ireland and the UK. We have found with SafeKit a simple and robust solution for high availability and synchronous replication between two servers with no data loss. With this software solution, we are not dependent on a specific and costly hardware clustering solution. It is a perfect tool to provide a software high availability option to an application of a software vendor."
20 SafeKit clusters are deployed on Windows and Linux.
Stéphane Guilmin, RATP, Project manager says:
"Automation of line 1 of the Paris subway is a major project for RATP, requiring a centralized command room (CCR) designed to resist IT failures. With SafeKit, we have three distinct advantages to meet this need. Firstly, SafeKit is a purely software solution that does not demand the use of shared disks on a SAN and network boxes for load balancing. It is very simple to separate our servers into separate machine rooms. Moreover, this clustering solution is homogeneous for our Windows and Linuxplatforms. SafeKit provides the three functions that we needed: load balancing between servers, automatic failover after an incident and real time data replication."
And also, Philippe Marsol, Atos BU Transport, Integration Manager says:
“SafeKit is a simple and powerful product for application high availability. We have integrated SafeKit in our critical projects like the supervision of Paris metro Line 4 (the control room) or Marseille Line 1 and Line 2 (the operations center). Thanks to the simplicity of the product, we gained time for the integration and validation of the solution and we had also quick answers to our questions with a responsive Evidian team.”
Over 30 SafeKit clusters are deployed on Windows with SQL Server.
Marc Pellas, CEO says:
"SafeKit perfectly meets the needs of a software vendor. Its main advantage is that it brings in high availability through a software option that is added to our own multi-platform software suite. This way, we are not dependent on a specific and costly hardware clustering solution that is not only difficult to install and maintain, but also differs according to client environments. With SafeKit, our firefighter call centers are run with an integrated software clustering solution, which is the same for all our customers, is user friendly and for which we master the installation up to after-sales support."
14 SafeKit clusters are deployed on Windows and Linux.
Alexandre Barth, Systems administrator says:
"Our production team implemented the SafeKit solution without any difficulty on 14 Windows and Linux clusters. Our critical activity is thus secure, with high-availability and load balancing functions. The advantages of this product are easy deployment and administration of clusters, on the one hand, and uniformity of the solution in the face of heterogeneous operating systems, on the other hand."
SafeKit High Availability Differentiators against Competition
Key differentiators of a mirror cluster with replication and failover
Evidian SafeKit mirror cluster with real-time file replication and failover
SafeKit high availability software on Windows and Linux saves on 1/ costly external shared or replicated storage, 2/ load balancing boxes, 3/ enterprise editions of OS and databases
SafeKit includes
all clustering features:
synchronous real-time file replication, monitoring of server / network / software failures, automatic
application
restart, virtual IP address switched in case of failure to reroute clients
The cluster configuration is very simple and made
with the .safe module.
by means of application modules.
New services and new replicated directories can be added to an existing application module
to complete a high availability solution
All the configuration of clusters is made using a simple centralized web administration console
There is no domain controller or active directory to configure as with Microsoft cluster
After a failure when a server reboots, the replication failback procedure
is fully automatic and the failed server reintegrates the cluster without stopping
the application
on the only remaining server
This is not the case with most replication solutions particularly with replication at the database level. Manual operations are required for resynchronizing a failed server.
The application
may even be stopped on the only remaining server during the resynchonization of the failed server
All SafeKit clustering features are working for 2 servers in remote sites. Replication requires an extended LAN type network (latency = performance of synchronous replication, bandwidth = performance of resynchronization after failure).
If both servers are connected to the same IP network through an extended LAN between two remote sites, the virtual IP address of SafeKit is working with rerouting at level 2
If both servers are connected to two different IP networks between two remote sites, the virtual IP address can be configured at the level of a load balancer with the "healh check" of SafeKit.
The secondary server is not dedicated to the restart of the primary server. The cluster can be active-active by running 2 different mirror modules
This is not the case with a fault-tolerant system where the secondary is dedicated to the execution of the same application synchronized at the instruction level
SafeKit implements a mirror cluster with replication and failover. But it imlements also
a farm cluster with load balancing and failover.
Thus a N-tiers architecture can be made highly available and load balanced with the same solution on
Windows and Linux (same installation, configuration, administration with the SafeKit console or with the command line interface). This is unique on the market
This is not the case with an architecture mixing different technologies for load balancing, replication and failover
SafeKit implements quick
application
restart in case of failure: around 1 mn or less (see RTO/RPO here)
Quick
application
restart is not ensured with full virtual machines replication. In case of hypervisor failure, a full VM must be rebooted on a new hypervisor with a recovery time depending on the OS reboot as with VMware HA or Hyper-V cluster
Key differentiators of a farm cluster with load balancing and failover
Evidian SafeKit farm cluster with load balancing and failover
The solution does not require load balancers or dedicated proxy servers above the farm for imlementing load balancing.
SafeKit is installed directly on the
application
servers in the farm. The load balancing is based on a standard virtual IP address/Ethernet MAC address and is working with physical servers or virtual machines on Windows and Linux without special network configuration
This is not the case with network load balancers
This is not the case with dedicated proxies on Linux
The solution includes all clustering features: virtual IP address,
load balancing on client IP address or on sessions,
monitoring of server / network / software failures,
automatic
application
restart with a quick revovery time and
a replication option with a mirror module
This is not the case with other load balancing solutions. They are able to make load balancing but they do not include a full clustering solution with restart scripts and
automatic
application
restart in case of failure. They do not offer a replication option
The cluster configuration is very simple and made
by means of application modules.
There is no domain controller or active directory to configure on Windows. The solution works on Windows and Linux
If servers are connected to the same IP network through an extended LAN between remote sites, the virtual IP address of SafeKit is working with load balancing at level 2
If servers are connected to different IP networks between remote sites, the virtual IP address can be configured at the level of a load balancer with the help of the SafeKit health check.
Thus you can implement load balancing but also all the clustering features of SafeKit, in particular monitoring and automatic recovery of the critical application on application servers
Thus a N-tiers architecture can be made highly available and load balanced with the same solution
on Windows and Linux (same installation, configuration, administration with the SafeKit console or with the command line interface). This is unique on the market
This is not the case with an architecture mixing different technologies for load balancing, replication and failover
Key differentiators of the SafeKit high availability technology
Application HA supports hardware failure and software failure with
a quick recovery time
(RTO around 1 mn or less).
Application HA requires to define restart scripts per application and folders to replicate (SafeKit application modules).
Full virtual machines HA supports only hardware failure with a VM reboot and a recovery time depending on the OS reboot.
No restart scripts to define with full virtual machines HA (SafeKit hyperv.safe or kvm.safe modules). Hypervisors are active/active with just multiple virtual machines.
No dedicated server with SafeKit.
Each server can be the failover server of the other one.
Software failure with restart in another OS environment.
Smooth upgrade of application and OS possible server by server (version N and N+1 can coexist)
Secondary server dedicated to the execution of the same application synchronized at the instruction level.
Software exception on both servers at the same time.
Smooth upgrade not possible
No dedicated proxy servers and no special network configuration are required in a SafeKit cluster for virtual IP addresses
Special network configuration is required in other clusters for virtual IP addresses. Note that SafeKit offers a health check adapted to load balancers
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The configuration of SafeKit is done on both nodes from a single browser.
To secure the web console, see 
OEM Software
SafeKit high availability software on Windows and Linux saves on 1/ costly external shared or replicated storage, 2/ load balancing boxes, 3/ enterprise editions of OS and databases
This is not the case with asynchronous replication
