Cisco 350 Series Administration Manual page 406

IP Configuration
IPv6 Management and Interfaces
Tunnel Sx350
Type
ISATAP Supported
Cisco 350, 350X and 550X Series Managed Switches, Firmware Release 2.4, ver 0.4
Additional Types of Tunnels
The following additional types of tunnels can be configured on the device:
• Manual Tunnel
- An IPv6 link local address is assigned to the ISATAP interface. The initial IP
address is assigned to the interface, which is then activated.
- If an ISATAP interface is active, the ISATAP router IPv4 address is resolved via
DNS by using ISATAP-to-IPv4 mapping. If the ISATAP DNS record is not
resolved, ISATAP host name-to-address mapping is searched in the host mapping
table.
- When the ISATAP router IPv4 address is not resolved via the DNS process, the
ISATAP IP interface remains active. The system does not have a default router for
ISATAP traffic until the DNS process is resolved.
This is a point-to-point definition. When creating a manual tunnel, you enter both the
source IP address (one of the device's IP addresses) and the destination IPv4 address.
• 6 to 4 Tunnel
6 to 4 is an automatic tunneling mechanism that uses the underlying IPv4 network as a
non-Broadcast multiple-access link layer for IPv6. Only one 6 to 4 tunnel is supported
on a device.
The 6to4 tunnel is supported only when IPv6 Forwarding is supported.
IPv6 Multicast is not supported on the 6to4 tunnel interface.
The switch automatically creates a 2002::/16 on-link prefix on the 6to4 tunnel. The
connected 2002::/16 route on the tunnel is added to the Routing Table as result of the
on-link prefix creation.
When the tunnel mode is changed from 6to4 to another mode, the on-link prefix and
connected routes are removed.
When the next hop outgoing interface is the 6to4 tunnel, the IPv4 address of the next
hop node is taken from the prefix 2002:WWXX:YYZZ::/48 of the IPv6 next hop IPv6
address, if it is global, and from the last 32 bits of the interface identifier of the IPv6
next hop IPv6 address, if it is link local.
The following table summarizes tunnel support in the various devices:
SG350x SG350XG/SX350X
Supported Supported
SG550X
Supported
16
SG550XG/SX550X
Supported
319