This topic describes how to configure detection of an
ICMP flood attack.
An ICMP flood typically occurs when an ICMP echo request overloads
the victim with many requests such that the ICMP echo request spends
all its resources responding until it can no longer process valid
network traffic. When enabling the ICMP flood protection feature,
you can set a threshold that, once exceeded, invokes the ICMP flood
attack protection feature.
To enable detection of an ICMP flood attack:
- Configure interfaces and assign an IP address to interfaces.
[edit]
user@host# set interfaces ge-0/0/1 unit 0 family inet address 192.0.2.0/24
user@host# set interfaces ge-0/0/3 unit 0 family inet address 198.51.100.0/24
- Configure security zones
trustZone and untrustZone and assign interfaces to them.[edit]
user@host# set security zones security-zone trustZone host-inbound-traffic system-services all
user@host# set security zones security-zone trustZone host-inbound-traffic protocols all
user@host# set security zones security-zone trustZone interfaces ge-0/0/1.0
user@host# set security zones security-zone untrustZone host-inbound-traffic system-services all
user@host# set security zones security-zone untrustZone host-inbound-traffic protocols all
user@host# set security zones security-zone untrustZone interfaces ge-0/0/3.0
- Configure security policies from
untrustZone to trustZone.[edit]
user@host# set security policies from-zone untrustZone to-zone trustZone policy policy1 match source-address any
user@host# set security policies from-zone untrustZone to-zone trustZone policy policy1 match destination-address any
user@host# set security policies from-zone untrustZone to-zone trustZone policy policy1 match application any
user@host# set security policies from-zone untrustZone to-zone trustZone policy policy1 then permit
user@host# set security policies default-policy deny-all
- Configure security screens and attach them to
untrustZone.[edit]
user@host# set security screen ids-option untrustScreen icmp flood
user@host# set security screen ids-option untrustScreen alarm-without-drop
user@host# set security zones security-zone untrustZone screen untrustScreen
- Configure syslog.
[edit]
user@host# set system syslog file syslog any any
user@host# set system syslog file syslog archive size 10000000
user@host# set system syslog file syslog explicit-priority
user@host# set system syslog file syslog structured-data
user@host# set security policies from-zone untrustZone to-zone trustZone policy policy1 then log session-init
user@host# set security policies from-zone untrustZone to-zone trustZone policy policy1 then log session-close
- Commit the configuration.
