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BigIron RX Series Configuration Guide
1011
53-1002253-01
IP source guard
35
IP source guard is used on client ports to prevent IP source address spoofing. Generally, IP source
guard is used together with DHCP snooping and Dynamic ARP Inspection on untrusted ports.
When IP source guard is first enabled, the client port allows only DHCP packets, and blocks all
other IP traffic. When the system learns a valid IP address on the port, the client port then allows IP
traffic. Client ports permit only the traffic with valid source IP addresses.
The system learns of a valid IP address from ARP. (For information on how the ARP table is
populated, refer to
“ARP entries”
on page 1002) When it learns a valid IP address, the system loads
a per-port IP ACL entry permitting the learned source IP address on the port.
When a new IP source entry binding on the port is created or deleted, the per-port IP ACL will be
recalculated and reapplied in hardware to reflect the change in IP source binding.
By default, if the IP source guard is enabled without any IP source binding on the port, an ACL that
denies all IP traffic is loaded on the port. Similarly, when the IP source guard is disabled, any IP
source per-port IP ACL will be removed from the interface.
Limits and restrictions
Current implementation with this feature has the following limitations:
•
Works only on routing and virtual interface ports, and does not support Layer 2 switching-only
ports in VLANs without an assigned IP address on the router.
•
Does not support auto-saving of the learnt ARP entries when DAI is enabled. You must
manually save the ARP entries before a reboot.
•
Does not provide CLI to disable check for source MAC and source IP in DAI.
Enabling IP source guard
DHCP Snooping should be configured before you enable the IP source guard feature.
The default setting is disabled. To enable IP source guard on an untrusted port, enter the following
commands.
BigIron RX(config)# interface ethernet 1/4
BigIron RX(config-if-e10000-1/4)# source guard enable
The commands change the CLI to the interface configuration level for port 1/4 and enable IP
source guard on the port.
Syntax: [no] source guard enable
Displaying learned IP addresses
To display all IP source bindings configured on all interfaces on a switch, enter a command such as
the following.
Syntax: show ip source guard ethernet <
port-num
>
BigIron RX#show ip source guard eth 5/20
IP source guard on ethernet 5/20: Enabled
Содержание BigIron RX Series
Страница 100: ...24 BigIron RX Series Configuration Guide 53 1002253 01 Logging on through the Web Management Interface 2 ...
Страница 192: ...116 BigIron RX Series Configuration Guide 53 1002253 01 Configuring authentication method lists 4 ...
Страница 228: ...152 BigIron RX Series Configuration Guide 53 1002253 01 Enabling WAN PHY mode support 6 ...
Страница 312: ...236 BigIron RX Series Configuration Guide 53 1002253 01 Displaying IP information 7 ...
Страница 356: ...280 BigIron RX Series Configuration Guide 53 1002253 01 Resetting LLDP statistics 9 ...
Страница 402: ...326 BigIron RX Series Configuration Guide 53 1002253 01 Transparent firewall mode 11 ...
Страница 432: ...356 BigIron RX Series Configuration Guide 53 1002253 01 SuperSpan 12 ...
Страница 500: ...424 BigIron RX Series Configuration Guide 53 1002253 01 MRP CLI example 14 ...
Страница 580: ...504 BigIron RX Series Configuration Guide 53 1002253 01 Configuring multicast traffic engineering 18 ...
Страница 591: ...BigIron RX Series Configuration Guide 515 53 1002253 01 Displaying traffic reduction 19 ...
Страница 592: ...516 BigIron RX Series Configuration Guide 53 1002253 01 Displaying traffic reduction 19 ...
Страница 598: ...522 BigIron RX Series Configuration Guide 53 1002253 01 Viewing Layer 2 ACLs 20 ...
Страница 656: ...580 BigIron RX Series Configuration Guide 53 1002253 01 Trunk formation 22 ...
Страница 754: ...678 BigIron RX Series Configuration Guide 53 1002253 01 Displaying RIP filters 24 ...
Страница 814: ...738 BigIron RX Series Configuration Guide 53 1002253 01 Displaying OSPF information 25 ...
Страница 932: ...856 BigIron RX Series Configuration Guide 53 1002253 01 Generalized TTL security mechanism support 26 ...
Страница 980: ...904 BigIron RX Series Configuration Guide 53 1002253 01 Clearing IS IS information 28 ...
Страница 1000: ...924 BigIron RX Series Configuration Guide 53 1002253 01 Using secure copy 30 ...
Страница 1088: ...1012 BigIron RX Series Configuration Guide 53 1002253 01 IP source guard 35 ...
Страница 1108: ...1032 BigIron RX Series Configuration Guide 53 1002253 01 Reading CDP packets 37 ...
Страница 1126: ...1050 BigIron RX Series Configuration Guide 53 1002253 01 Clearing sFlow statistics 39 ...
Страница 1140: ...1064 BigIron RX Series Configuration Guide 53 1002253 01 802 1s Multiple Spanning Tree Protocol 40 ...
Страница 1324: ...1248 BigIron RX Series Configuration Guide 53 1002253 01 Displaying OSPFv3 information 48 ...
Страница 1363: ...BigIron RX Series Configuration Guide 1287 53 1002253 01 Continuous System Monitor 51 ...
Страница 1364: ...1288 BigIron RX Series Configuration Guide 53 1002253 01 Continuous System Monitor 51 ...
Страница 1404: ...1328 BigIron RX Series Configuration Guide 53 1002253 01 Commands That Require a Reload D ...
Страница 1458: ...1382 BigIron RX Series Configuration Guide 53 1002253 01 VSRP E ...