System information

Basic Configuration
3-19
3
• Manual Configuration – Manually configures an IPv6 address.
• IPv6 Address – An IPv6 address can be configured in any of these ways:
- A link-local address can be manually configured by specifying the entire
address in the IPv6 Address field, and selecting the Address Type “Link
Local.” The network prefix length is fixed at 64 bits and cannot be changed.
- A global unicast address can be configured by specifying the network prefix
and the length of the prefix (in the IPv6 Address and Prefix Length fields), and
then selecting the Address Type “EUI-64” to automatically create the host
portion of the address in the low order 64 bits based on the modified EUI-64
interface identifier.
- A global unicast address can be manually configured by specifying the full
address and network prefix length (in the IP Address and Prefix Length fields),
and selecting the Address Type “Global.”
- A global unicast address can also be set by selecting a preconfigured general
prefix for the network portion of the address from the Based on General Prefix
scroll-down list and marking the check box next to this field to enable your
choice (see “Configuring an IPv6 General Network Prefix” on page 3-22), and
then specifying the address (in the IPv6 Address field) and the full network
prefix length which includes the general prefix and any contiguous bits from
the left of the address that are appended to the network prefix (in the Prefix
Length field).
• Prefix Length – A decimal value indicating how many contiguous bits (from the
left) of the address comprise the prefix (i.e., the network portion of the address).
When used with a general network prefix to configure a global unicast address,
this length includes both that specified by the general prefix and any contiguous
prefix bits (from the left of the specified address) that exceed the length of the
general prefix. If the prefix length specified by this parameter is shorter than the
general prefix, then the length of the general prefix takes precedence.
• Based on General Prefix – Defines a general prefix for the network segment of
the address (see “Configuring an IPv6 General Network Prefix” on page 3-22).
When configuring a global unicast address based on a general network prefix,
the Prefix Length includes both that specified by the general prefix and any
number of subsequent prefix bits that exceed the length of the general prefix.
Therefore, depending on the value specified by the Prefix Length, some of the
address bits entered in the IPv6 Address field may be appended to the general
prefix. However, if the Prefix Length is shorter than the general prefix, then the
length of the general prefix takes precedence, and some of the address bits
entered in the IPv6 Address field will be ignored.
• Address Type – Defines the address type configured for this interface.
• Link Local – Configures an IPv6 link-local address.
- The address prefix must be FE80.
- You can configure only one link-local address per interface.
- The specified address replaces a link-local address that was automatically
generated for the interface.