Here are some of the pre-requisites for OpManager implementation :

1. Server (Physical\Virtual) to install OpManager application (One server for a standalone and multiple servers for Enterprise edition) according to the hardware requirement below,

https://www.manageengine.com/network-monitoring/help/hardware-and-software-requirements.html

2. Specify if you need OpManager to be installed in a specific web server port, Else we will use the default 8080 Webserver port.

3. If your backend Database is MSSQL, Keep the DB server and SQL credentials ready to create database for OpManager.

3. Gather the required credentials for monitoring the devices.

• SNMP 

• WMI 
  

• CLI(TELNET\SSH) 

• VMware (make sure you have the correct https credentials.)

4. If there is any firewall, make sure the SNMP (161), WMI (135, 445 and any random port between 5000-6000) is open.

5. Here are the ports which need to be opened in the firewall. 

 SNMP-161(UDP) - Bidirectional

SNMP Traps - 162(UDP) - Unidirectional (From monitored device to OpManager server)

WMI - 135 & 445, 5000 - 6000(TCP) - Bidirectional

Telnet - 23(TCP) - Bidirectional

SSH - 22(TCP) - Bidirectional

ICMP - We use to check the availability status and to add a device. - Bidirectional

Default syslog port 514(UDP) - Unidirectional (From monitored device to OpManager server)

6. Prepare the entire Inventory list with Device IP which has to be monitored in OpManager(Location-wise in case of Enterprise Edition).

7. Basic Network diagram to create Business Views, Topology and Groups.

8. In case of AD login needed for the application, Need the Domain Controller details.

9. Mail server details for Mail server configuration.

10. For Netflow, Please configure flows on all the L3 interfaces which you need to monitor. Please find the link for the flow export configuration,

https://www.manageengine.com/products/netflow/help/configuring-flow-export.html

11. Device SSH\TELNET credential needed for device backup with NCM module.

12. Threshold values have to be decided for all monitors.