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BigIron RX Series Configuration Guide
999
53-1002253-01
Displaying statistics due DoS attacks
34
•
If the SYN bit is set and the sequence number is an exact match to the next expected
sequence, the device sends an ACK segment to the peer. Before sending the ACK segment, the
software subtracts one from the value being acknowledged.
•
If the SYN bit is set and the sequence number is acceptable, the device sends an
acknowledgement (ACK) segment to the peer.
The TCP security enhancement is enabled by default. To disable it, refer to
“Disabling the TCP
security enhancement”
on page 999.
Protecting against a blind injection attack
In a blind TCP injection attack, a perpetrator tries to inject or manipulate data in a TCP connection.
To reduce the chances of a blind injection attack, perform an additional check on all incoming TCP
segments.
This TCP security enhancement is enabled by default. To disable it, refer to
“Disabling the TCP
security enhancement”
on page 999.
Disabling the TCP security enhancement
The TCP security enhancement is automatically enabled. If necessary, you can disable this feature.
When you disable this feature, the device reverts to the original behavior.
To disable the TCP security enhancement, enter the following command at the Global CONFIG level
of the CLI.
BigIron RX(config)# no ip tcp tcp-security
To re-enable the TCP security enhancement once it has been enabled, enter the following
command.
BigIron RX(config)# ip tcp tcp-security
Syntax: [no] ip tcp tcp-security
Displaying statistics due DoS attacks
To display information about ICMP and TCP SYN packets dropped, passed, and block because burst
thresholds were exceeded.
The display shows the following.
BigIron RX(config-if-e1000-3/5)# show statistics dos-attack
Collecting transit DOS attack statistic for port 3/5... Completed successfully.
------ DOS Attack Prevention Statistics ------
Port Packet Drop Count Packet Pass Count Port Block Count
----- ----------------- ------------------ ----------------
3/5 12479732 436372 232
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 ...