Have block 123 port to internet on router.
Use access-list like
interface GigabitEthernet0/1
ip address zz.zz.zz.zz 255.255.255.248
ip access-group INB3 in
no ip redirects
no ip unreachables
no ip proxy-arp
ip access-list extended INB3
deny udp any host zz.zz.zz.zz eq ntp
deny udp any host zz.zz.zz.zz eq snmp
permit ip any any
and use:
access-list 2 remark "SNMP RO access"
access-list 2 permit yy.yy.yy.yy
access-list 2 deny any log
access-list 44 remark ACCESS SYNC to NTP Serv
access-list 44 permit xx.xx.xx.xx
access-list 44 deny any log
ntp access-group peer 44
But the snmp & ntp ports are not blocked.
Any idea, what might be the reseason.
Thank You in y Advance!
