tproxy To Monitor gRPC And TCP Connections

A cli tool to proxy and analyze TCP connections.

• monitoring gRPC connections, when to connect and when to reconnect
• monitoring MySQL connection pools, how many connections and figure out the lifetime policy
• monitoring any TCP connections on the fly

Installation

$ go install github.com/kevwan/tproxy@latest

Or use docker images:

$ docker run --rm -it -p : -p : kevinwan/tproxy:v1 tproxy -l 0.0.0.0 -p -r host.docker.internal:

For arm64:

$ docker run –rm -it -p : -p : kevinwan/tproxy:v1-arm64 tproxy -l 0.0.0.0 -p -r host.docker.internal:

On Windows, you can use scoop:

$ scoop install tproxy

Usages

$ tproxy --help
Usage of tproxy:
-d duration
the delay to relay packets
-down int
Downward speed limit(bytes/second)
-l string
Local address to listen on (default "localhost")
-p int
Local port to listen on, default to pick a random port
-q Quiet mode, only prints connection open/close and stats, default false
-r string
Remote address (host:port) to connect
-s Enable statistics
-t string
The type of protocol, currently support http2, grpc, redis and mongodb
-up int
Upward speed limit(bytes/second)

Learn TCP/Connections here

Examples

Monitor gRPC connections

$ tproxy -p 8088 -r localhost:8081 -t grpc -d 100ms

• listen on localhost and port 8088
• redirect the traffic to localhost:8081
• protocol type to be gRPC
• delay 100ms for each packets

Monitor MySQL connections

$ tproxy -p 3307 -r localhost:3306

Check the connection reliability (Retrans rate and RTT)

$ tproxy -p 3307 -r remotehost:3306 -s -q

Learn the connection pool behaviors

$ tproxy -p 3307 -r localhost:3306 -q -s

Download tproxy