How to check the speed of the communication channel in the presence of a server on FreeBSD and cisco routers?

Question

PHP

Good afternoon!
I have about 2000 routers in the region. The bulk - the manufacturer cisco. All have a point-to-point connection with the head office (not quite right, but we will accept it to simplify the task). To monitor them, at the central point (head control) there is a FreeBSD server with a standard set: apache, php, mysql, zabbix, and handwritten software is running on it, which can do what zabbix cannot. Polling is done using PHP via SNMP and is entered into the database. There was a need once a week or a month to test the communication channel in both directions for compliance with the actual channel speed and the one set by the provider. The server no longer sees the device behind the router, so it can:
1. communicate with remote routers via SNMP, FTP/TFTP, Telnet
2. Initiate any processes on the central routers at this end via SNMP or Telnet.
It is supposed to start testing in turn during non-working hours to evaluate the incoming and outgoing channel to the points.
Are there any options that allow me to accurately test the speed of the channel for my situation?

Answer 1

There is an undocumented ttcp utility on the cisco. There is a similar utility in the ports: /usr/ports/benchmarks/ttcp. In theory, they should work together :-) But by default, it overtakes only 16 MB for the test, the channel may not have time to swing to the full. There is information that you can play around with the rcvwndsize parameter so that more traffic is pumped, but I have not worked with this, so I can not confirm.

Answer 2

Exist. SSH into /dev/null some amount of data. Determine the exact volume yourself, based on the reference throughput and the required inspection depth. Only download one file, otherwise the speed will be lower.
You can do this:
Stage 1. Copy the file from the server to the NVRAM of the device.
Step 2. Copy it back to the server, to /dev/null.
Stage 3. See readings in zabbix.