macOS の時刻がずれる (time.apple.com 側の問題)

様々なコマンドを使って確認するのは面倒臭いので python スクリプトを作りました。

check_time_server.py として保存してください。

#!/usr/bin/env python3

import argparse
import socket
import sys

CHECK = {None: '--', False: 'NG', True: 'OK'}
PORT = 123

flag_dryrun = False
flag_verbose = False
timeout_second = 1
message = print


def verbose(msg):
    return flag_verbose and message(msg)


def try_sntp(addr):
    pkt = bytearray(4*12)
    pkt[0] = (3 << 3) | 3

    ipaddr = addr[4][0]
    sock = socket.socket(family=addr[0], type=addr[1], proto=socket.IPPROTO_UDP)
    if timeout_second > 0:
        sock.settimeout(timeout_second)
    try:
        sres = sock.sendto(pkt, (ipaddr, PORT))
        rres = sock.recvfrom(64)
    except OSError as e:
        message(f'Error: {e} ({ipaddr})')
        sock.close()
        return False
    sock.close()
    return True


def check_server(hostname):
    message(f'Server: {hostname}')
    addrs = socket.getaddrinfo(hostname, PORT, proto=socket.IPPROTO_UDP)
    verbose('Address:')
    hostmap = [{}, {}]
    for addr in addrs:
        ipaddr = addr[4][0]
        try:
            sname = socket.gethostbyaddr(ipaddr)[0]
        except OSError as e:
            verbose(f'Error: gethostbyaddr("{ipaddr}"): {e}')
            sname = hostname
        verbose(f'  {ipaddr:39} : {sname}')
        success = None
        if not flag_dryrun:
            success = try_sntp(addr)
        hmap = hostmap[int(addr[0] == socket.AF_INET6)]
        if sname not in hmap:
            hmap[sname] = []
        hmap[sname].append([ipaddr, success])
    for host in sorted(set(sum((list(h.keys()) for h in hostmap), []))):
        message('\n'.join([
            f'{host}:',
            *[f'  {CHECK[check]} - {addr}' for hmap in hostmap
              for addr, check in sorted(hmap.get(host, []))]]))


if __name__ == '__main__':
    parser = argparse.ArgumentParser()
    parser.add_argument('-v', '--verbose', action='store_true')
    parser.add_argument('-d', '--dryrun', action='store_true')
    parser.add_argument('-t', '--timeout', type=int, default=1)
    parser.add_argument('server', metavar='SERVER')
    args = parser.parse_args()
    flag_dryrun = args.dryrun
    flag_verbose = args.verbose
    timeout_second = args.timeout
    check_server(args.server)

次のような結果が得られるでしょう。

$ python3 check_time_server.py time.apple.com
Server: time.apple.com
Error: timed out (2403:300:a0c:4000::1f2)
Error: timed out (2403:300:a0c:3000::1e2)
Error: timed out (2403:300:a16:4000::1f2)
jptyo5-ntp-001.aaplimg.com:
  OK - 17.253.68.125
jptyo5-ntp-002.aaplimg.com:
  OK - 17.253.68.253
  NG - 2403:300:a0c:4000::1f2
jptyo5-ntp-003.aaplimg.com:
  NG - 2403:300:a0c:3000::1e2
jptyo5-ntp-004.aaplimg.com:
  OK - 17.253.68.251
krsel6-ntp-002.aaplimg.com:
  NG - 2403:300:a16:4000::1f2
$ python3 check_time_server.py time.apple.com
Server: time.apple.com
Error: timed out (2403:300:a0c:4000::1f2)
Error: timed out (2403:300:a0c:3000::1e2)
jptyo5-ntp-001.aaplimg.com:
  OK - 17.253.68.125
jptyo5-ntp-002.aaplimg.com:
  OK - 17.253.68.253
  NG - 2403:300:a0c:4000::1f2
jptyo5-ntp-003.aaplimg.com:
  NG - 2403:300:a0c:3000::1e2
jptyo5-ntp-004.aaplimg.com:
  OK - 17.253.68.251
krsel6-ntp-002.aaplimg.com:
  OK - 2403:300:a16:4000::1f2

ちなみに、 ntp.nict.jp, time.google.com , time.aws.com など公開 NTP で NG が出るのは見た事がないです。