1) Peer – permits router to respond to NTP requests and accept NTP updates. NTP control queries are also accepted. This is the only class which allows a router to be synchronized by other devices.
2) Serve – permits router to reply to NTP requests, but rejects NTP updates (e.g. replies from a server or update packets from a peer). Control queries are also permitted.
3) Serve-only – permits router to respond to NTP requests only. Rejects attempt to synchronize local system time, and does not access control queries.
4) Query-only – only accepts NTP control queries. No response to NTP requests are sent, and no local system time synchronization with remote system is permitted.

ntp access-group peer 35
ntp access-group serve 30
ntp access-group serve-only 30
ntp access-group query-only 30
ntp server 144.210.60.118

Standard IP access list 35
9 permit 144.210.60.118 (114 matches)
10 permit 152.2.133.54
20 permit 10.132.112.151
30 permit 10.100.23.254
40 permit 144.210.199.11
50 permit 144.210.190.91
60 permit 144.210.230.24
70 permit 209.114.111.1
80 deny any (5371 matches)
corsw02a-(config)#do show access-l 30
Standard IP access list 30
10 deny any (16113 matches)

clock timezone CET +1 0
clock summer-time CEST recurring