Now that you know you can monitor your network traffic through STG how do you go and configure it? You can use a simple program called GetIf to search for what ports you need to monitor on your SonicWall or other SNMP enabled Routers.
Make sure to switch the Host Name over to your SonicWall Appliance and the SNMP Get name (System>Administration, then towards the bottom of the screen under Advanced Management. Click on Configure after the Check Box and Enable SNMP, the value in the “Get Community Name” section).
Once you have this information filled in you can click on start and it should update the information (depending on how you have the SonicWall or other SNMP Router Configured). If it is all entered properly and setup properly on the SonicWall then at the very least you should get the SysDescr (System Description) section, this lists what type of SonicWall appliance you are monitoring and more than likely what OS (version number and standard or enhanced).
After verifying that GetIf is able to communicate properly with the SonicWall, switch over to the Interfaces tab and click on start again to pull down the Interface information for your particular setup.
This will show you what interface number is assigned to which interface. Some of the SonicWalls have the first interface 1 assigned to the WAN port and interface 2 assigned to the Loopback. Others have interface 1 assigned to the loopback port and interface 2 assigned to the X0 interface. Finally on higher end units you can switch what the various ports are doing and make up to 2 WAN ports for failover/load balancing, setup a DMZ, VLans, and other separators. You can also use this information to look at other SNMP Enabled Routers.
Once you have figured out the port numbers that you want to monitor you can use GetIf to help figure out the path you need to enter into STG settings (F9) so that you can monitor the inbound and outbound traffic. The next step is to switch over to the MBrowser tab and “Walk the MIBs” (browse through the Management Information Base) on the SonicWall or other SNMP enabled Router. The two pieces of information you are looking for are the ifInOctets and ifOutOctets. When you walk the MIB on a SonicWall, it will give you a path where this information is stored. In the case of a SonicWall it is located at the MIB of .220.127.116.11.18.104.22.168.1.10 or .iso.org.dod.internet.mgmt.mib-2.interfaces.ifTable.ifEntry.ifInOctets (inbound) and .22.214.171.124.126.96.36.199.1.16 or .iso.org.dod.internet.mgmt.mib-2.interfaces.ifTable.ifEntry.ifOutOctets (outbound).
You can plug that information into the STG Settings like below, adjusting the Interface number to monitor what you want to monitor (Primary WAN, Secondary WAN, WLAN, etc):
*Please note that we have found one issue on the SonicWalls. You can monitor primary/secondary WAN settings, but for both you will need to target the Primary WAN IP and then switch Ports over to the secondary. We have contacted SonicWall and mentioned this “bug” and they are working on the problem, but it has not currently been updated / implemented.
Then all you will need to do is adjust your Max Rate to fit your line speed (this one is currently set to the equivalent of a T1 1.6 Mbps if you want to mirror this one).