Edge-Core AS5700-54X, Cli Reference Manual, Page: 318 / 1116

Chapter 8
| General Security Measures
IPv6 Source Guard
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This command checks the VLAN ID, IPv6 global unicast source IP address, and
port number against all entries in the binding table. Use the
no ipv6 source
guard command to disable this function on the selected port.
◆
After IPv6 source guard is enabled on an interface, the switch initially blocks all
IPv6 traffic received on that interface, except for ND packets allowed by ND
snooping and DHCPv6 packets allowed by DHCPv6 snooping. A port access
control list (ACL) is applied to the interface. Traffic is then filtered based upon
dynamic entries learned via ND snooping or DHCPv6 snooping, or static
addresses configured in the source guard binding table. The port allows only
IPv6 traffic with a matching entry in the binding table and denies all other IPv6
traffic.
◆
Table entries include a MAC address, IPv6 global unicast address, lease time,
entry type (Static-IPv6-SG-Binding, Dynamic-ND-Snooping, Dynamic-DHCPv6-
Snooping), VLAN identifier, and port identifier.
◆
Static addresses entered in the source guard binding table with the ipv6
source-guard binding command are automatically configured with an infinite
lease time. Dynamic entries learned via DHCPv6 snooping are configured by
the DHCPv6 server itself.
◆
If IPv6 source guard is enabled, an inbound packet’s source IPv6 address will be
checked against the binding table. If no matching entry is found, the packet
will be dropped.
◆
Filtering rules are implemented as follows:
■
If ND snooping and DHCPv6 snooping are disabled, IPv6 source guard will
check the VLAN ID, source IPv6 address, and port number. If a matching
entry is found in the binding table and the entry type is static IPv6 source
guard binding, the packet will be forwarded.
■
If ND snooping or DHCPv6 snooping is enabled, IPv6 source guard will
check the VLAN ID, source IP address, and port number. If a matching entry
is found in the binding table and the entry type is static IPv6 source guard
binding, dynamic ND snooping binding, or dynamic DHCPv6 snooping
binding, the packet will be forwarded.
■
If IPv6 source guard is enabled on an interface for which IPv6 source
bindings (dynamically learned via ND snooping or DHCPv6 snooping, or
manually configured) are not yet configured, the switch will drop all IPv6
traffic on that port, except for ND packets and DHCPv6 packets allowed by
DHCPv6 snooping.
■
Only IPv6 global unicast addresses are accepted for static bindings.