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Using ping, tracert, and system debugging ··············································································································· 1
Ping
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Using a ping command to test network connectivity ····························································································1
Ping example ····························································································································································1
Tracert ················································································································································································3
Prerequisites ······························································································································································4
Using a tracert command to identify failed or all nodes in a path ·····································································4
Tracert example ························································································································································4
System debugging ····························································································································································5
Debugging information control switches················································································································6
Debugging a feature module ··································································································································6
Configuring NTP ·························································································································································· 8
Overview············································································································································································8
How NTP works ························································································································································8
NTP architecture ·······················································································································································9
Association modes ················································································································································ 10
NTP security ··························································································································································· 12
Protocols and standards ······································································································································· 13
Configuration restrictions and guidelines ···················································································································· 13
Configuration task list ···················································································································································· 13
Enabling the NTP service ·············································································································································· 13
Configuring NTP association modes···························································································································· 13
Configuring NTP in client/server mode ·············································································································· 14
Configuring NTP in symmetric active/passive mode ························································································ 14
Configuring NTP in broadcast mode ·················································································································· 15
Configuring NTP in multicast mode····················································································································· 16
Configuring access control rights ································································································································· 17
Configuring NTP authentication ··································································································································· 17
Configuring NTP authentication in client/server mode ····················································································· 17
Configuring NTP authentication in symmetric active/passive mode ······························································· 19
Configuring NTP authentication in broadcast mode ························································································· 21
Configuring NTP authentication in multicast mode ··························································································· 23
Configuring NTP optional parameters ························································································································· 25
Specifying the source interface for NTP messages ···························································································· 25
Disabling an interface from receiving NTP messages ······················································································· 26
Configuring the maximum number of dynamic associations ············································································ 26
Configuring the local clock as a reference source ····································································································· 27
Displaying and maintaining NTP ································································································································· 27
NTP client/server mode configuration example ········································································································· 28
IPv6 NTP client/server mode configuration example································································································· 29
NTP symmetric active/passive mode configuration example ··················································································· 30
IPv6 NTP symmetric active/passive mode configuration example ··········································································· 32
NTP broadcast mode configuration example ············································································································· 34
NTP multicast mode configuration example
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IPv6 NTP multicast mode configuration example ······································································································· 39
Configuration example for NTP client/server mode with authentication
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Configuration example for NTP broadcast mode with authentication ····································································· 44