действие зеркала / перенаправления (mirror/redirect action)
Имя (Name)
mirred - mirror/redirect action
Синопсис (Synopsis)
tc
... action mirred
DIRECTION ACTION [ index
INDEX ] dev
DEVICENAME
DIRECTION := { ingress
| egress
}
ACTION := { mirror
| redirect
}
Описание (Description)
The mirred
action allows packet mirroring (copying) or
redirecting (stealing) the packet it receives. Mirroring is what
is sometimes referred to as Switch Port Analyzer (SPAN) and is
commonly used to analyze and/or debug flows.
Параметры (Options)
ingress
egress
Specify the direction in which the packet shall appear on
the destination interface.
mirror
redirect
Define whether the packet should be copied (mirror
) or
moved (redirect
) to the destination interface.
index
INDEX
Assign a unique ID to this action instead of letting the
kernel choose one automatically. INDEX is a 32bit
unsigned integer greater than zero.
dev
DEVICENAME
Specify the network interface to redirect or mirror to.
Примеры (Examples)
Limit ingress bandwidth on eth0 to 1mbit/s, redirect exceeding
traffic to lo for debugging purposes:
# tc qdisc add dev eth0 handle ffff: ingress
# tc filter add dev eth0 parent ffff: u32 \
match u32 0 0 \
action police rate 1mbit burst 100k conform-exceed pipe \
action mirred egress redirect dev lo
Mirror all incoming ICMP packets on eth0 to a dummy interface for
examination with e.g. tcpdump:
# ip link add dummy0 type dummy
# ip link set dummy0 up
# tc qdisc add dev eth0 handle ffff: ingress
# tc filter add dev eth0 parent ffff: protocol ip \
u32 match ip protocol 1 0xff \
action mirred egress mirror dev dummy0
Using an ifb
interface, it is possible to send ingress traffic
through an instance of sfq
:
# modprobe ifb
# ip link set ifb0 up
# tc qdisc add dev ifb0 root sfq
# tc qdisc add dev eth0 handle ffff: ingress
# tc filter add dev eth0 parent ffff: u32 \
match u32 0 0 \
action mirred egress redirect dev ifb0
Смотри также (See also)
tc(8), tc-u32(8)