pfc_counter_diff.py

# -*- coding: utf-8 -*-
# Copyright (c) 2016 Arista Networks, Inc.  All rights reserved.
# Arista Networks, Inc. Confidential and Proprietary.

"""

Display PFC counter delta.  First run will simply display current values

Requires:

paramiko (For SSH) - pip install paramiko
requests (For eAPI) - pip install requests
arcomm (2.0+) - pip install arcomm

Caveats:

This script does not handle counter resets/flips, so it is possible to get a
negative value

"""

from __future__ import (absolute_import, division, print_function,
                        unicode_literals)

import arcomm
import argparse
import getpass
import tempfile
import os
import json

__version__ = '0.1.0'
__author__ = 'Jesse Mather <[email protected]'

def parse_args():
    parser = argparse.ArgumentParser(prog="arcomm")
    arg = parser.add_argument

    arg("endpoints", nargs="+",
        help="Specifies one or more hosts to collect counter data")
    arg("-v", "--version", action="store_true", help="Display version info")
    arg("-u", "--username", help="Specifies the username on the switch")
    arg("-p", "--password", help="Specifies users password.")
    arg("--protocol", default="ssh", help="Specifies the protocol (ssh or eapi)")

    return parser.parse_args()

def main():
    args = parse_args()

    tempdir = tempfile.gettempdir()

    if args.version:
        parser.exit(0, __version__ + "\n")

    if not args.username:
        args.username = getpass.getuser()

    if args.password is None:
        args.password = getpass.getpass('Password: ')

    creds = arcomm.BasicCreds(args.username, args.password)

    script = ['show interfaces priority-flow-control counters']

    for response in arcomm.batch(args.endpoints, script, creds=creds,
                                 protocol=args.protocol):

        # generate path to snapshot file
        filename = 'pfc-counters-snapshot-{}'.format(response.host)
        path = os.path.join(tempdir, filename)

        prev = {}

        if os.path.exists(path):
            with open(path, 'r') as fh:
                prev = json.loads(fh.read())

        counters = {}

        for line in str(response[0]).splitlines():
            if line.startswith('Port'):
                continue

            port, rx, tx = line.split()
            rx = int(rx)
            tx = int(tx)

            prx, ptx = [0, 0]
            if port in prev:
                prx, ptx = prev[port]

            print("{}\t{}\t{}\t{}".format(response.host, port, tx - ptx, rx - prx))

            counters[port] = [int(rx), int(tx)]

        # overwrite the old snapshot
        with open(path, 'w') as fh:
            fh.write(json.dumps(counters))

if __name__ == '__main__':
    main()