TC-MATCHALL(8)

💅 tc-matchall(8) — Match-all classifier in tc(8) 💅

okay bestie, this is the manual page for matchall, the tc filter that catches every single packet 🦋 no exceptions, no cap. main character energy fr 👑

✨ NAME ✨

matchall — traffic control filter that matches every packet 💖

🎀 SYNOPSIS 🎀

tc filter ... matchall [ skip_sw | skip_hw  ] [ action ACTION_SPEC ] [
        classid CLASSID ]

🌸 DESCRIPTION 🌸

okay so the matchall filter lets you classify every packet that flows through the port, and then run an action on it. it's giving total packet domination 💅✨

🦋 OPTIONS 🦋

• action ACTION_SPEC — slap an action from the generic actions framework onto the packets that match 🔥
• classid CLASSID — toss the matching packets into the class identified by CLASSID 🧚
• skip_sw — don't process the filter in software 💀 if the hardware can't offload this filter, or TC offload isn't turned on for the interface, the operation will fail. no backup plan, bestie 😭
• skip_hw — don't process the filter in hardware 🙈

🍓 EXAMPLES 🍓

okay these are the iconic ones 🫶

🪞 Ingress mirroring from eth1 to eth2

say you want to mirror everything coming in on port eth1 over to port eth2:

tc qdisc  add dev eth1 handle ffff: clsact
tc filter add dev eth1 ingress                \
        matchall skip_sw                      \
        action mirred egress mirror           \
        dev eth2

the first command creates a clsact qdisc with handle ffff: on device eth1, and the second attaches a matchall filter on it that mirrors the packets to device eth2 for ingress. ate, no crumbs 💜

🪞 Egress mirroring from eth1 to eth2

now the reverse: mirroring everything going out of eth1 to eth2:

tc qdisc add dev eth1 handle ffff: clsact
tc filter add dev eth1 egress                  \
        matchall skip_sw                       \
        action mirred egress mirror            \
        dev eth2

same vibe as before. the first command makes a clsact qdisc with handle ffff: on device eth1, and the second attaches a matchall filter that mirrors the packets to device eth2 for egress 🌈

🧁 Sampling one of every 100 packets into psample group 12

want a little taste instead of the whole buffet? sample one of every 100 packets flowing into eth0 and send them to psample group 12:

tc qdisc add dev eth0 handle ffff: ingress
tc filter add dev eth0 parent ffff: matchall \
     action sample rate 100 group 12

🔗 SEE ALSO 🔗

tc(8),

that's the whole page, bestie 🎀 source: iproute2, dated 21 Oct 2015, and yes it's still giving 💖🧚