HP VPN Firewall Appliances VPN Configuration Guide
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Contents
Configuring GRE ·························································································································································· 1
Overview ············································································································································································ 1
GRE encapsulation format ······································································································································· 1
GRE encapsulation and de-encapsulation ············································································································· 2
GRE security features ··············································································································································· 2
GRE application scenarios ······································································································································ 3
Protocols and standards ·········································································································································· 4
Configuring a GRE over IPv4 tunnel in the Web interface ··························································································· 5
Configuration prerequisites ····································································································································· 5
Recommended configuration procedure ················································································································ 5
Creating a GRE over IPv4 tunnel interface ············································································································ 5
GRE over IPv4 tunnel configuration example ········································································································ 7
Configuring a GRE tunnel at the CLI ···························································································································· 10
Configuring a GRE over IPv4 tunnel ··················································································································· 10
Configuring a GRE over IPv6 tunnel ··················································································································· 12
Displaying GRE······················································································································································ 14
GRE over IPv4 tunnel configuration example ····································································································· 14
GRE over IPv6 tunnel configuration example ····································································································· 17
Troubleshooting GRE ····················································································································································· 20
Configuring a point-to-multipoint GRE tunnel ··········································································································· 21
Overview ········································································································································································· 21
How a P2MP GRE tunnel operates ······················································································································ 21
GRE tunnel backup at a branch ··························································································································· 23
GRE tunnel backup at the headquarters ············································································································· 23
Advantages and restrictions of the P2MP GRE tunnel technology ··································································· 24
Configuring a P2MP GRE tunnel in the Web interface ······························································································ 25
Configuration prerequisites ·································································································································· 25
Recommended configuration procedure ············································································································· 25
Configuring a P2MP GRE tunnel interface ········································································································· 25
Displaying information about established P2MP GRE tunnels·········································································· 27
Basic P2MP GRE tunnel configuration example ································································································· 28
Configuration example for P2MP GRE tunnel backup at the headquarters ···················································· 31
Configuration example for P2MP GRE tunnel backup at a branch ································································· 40
Configuring a P2MP GRE tunnel at the CLI ················································································································· 47
Configuring a P2MP GRE tunnel ························································································································· 47
Displaying and maintaining P2MP GRE tunnels ································································································ 49
Basic P2MP GRE tunnel configuration example ································································································· 49
Configuration example for backing up a P2MP GRE tunnel at the headquarters ········································· 51
Configuration example for backing up a P2MP GRE tunnel at a branch ······················································· 55
Configuring tunneling ················································································································································ 59
Overview ········································································································································································· 59
IPv6 over IPv4 tunneling ······································································································································· 59
IPv4 over IPv4 tunneling ······································································································································· 62
IPv4 over IPv6 tunneling ······································································································································· 63
IPv6 over IPv6 tunneling ······································································································································· 66
Protocols and standards ······································································································································· 67
Tunneling configuration task list ··································································································································· 67
Configuring a tunnel interface ······································································································································ 67