CLI Guide

• If the tunnel mode is ipv6ip (where ip address over tunnel interface is not
possible).
To ping the unnumbered tunnels the logical address route information should be
present in both the ends.
NOTE: The ipv6 unnumbered command can specify an interface name that
does not yet exist, or does not yet have a configured IPv6 address. But the
tunnel interface will not go operationally up until it has determined a logical
address to use of at least one address family.
Tunneling
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