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diff --git a/man/man8/tc-simple.8 b/man/man8/tc-simple.8 new file mode 100644 index 0000000..f565755 --- /dev/null +++ b/man/man8/tc-simple.8 @@ -0,0 +1,98 @@ +.TH "Simple action in tc" 8 "12 Jan 2015" "iproute2" "Linux" + +.SH NAME +simple - basic example action +.SH SYNOPSIS +.in +8 +.ti -8 +.BR tc " ... " "action simple" +[ +.BI sdata " STRING" +] [ +.BI index " INDEX" +] [ +.I CONTROL +] + +.ti -8 +.IR CONTROL " := {" +.BR reclassify " | " pipe " | " drop " | " continue " | " ok " }" + +.SH DESCRIPTION +This is a pedagogical example rather than an actually useful action. Upon every access, it prints the given +.I STRING +which may be of arbitrary length. +.SH OPTIONS +.TP +.BI sdata " STRING" +The actual string to print. +.TP +.BI index " INDEX" +Optional action index value. +.TP +.I CONTROL +Indicate how +.B tc +should proceed after executing the action. For a description of the possible +.I CONTROL +values, see +.BR tc-actions (8). +.SH EXAMPLES +The following example makes the kernel yell "Incoming ICMP!" every time it sees +an incoming ICMP on eth0. Steps are: +.IP 1) 4 +Add an ingress qdisc point to eth0 +.IP 2) 4 +Start a chain on ingress of eth0 that first matches ICMP then invokes the +simple action to shout. +.IP 3) 4 +display stats and show that no packet has been seen by the action +.IP 4) 4 +Send one ping packet to google (expect to receive a response back) +.IP 5) 4 +grep the logs to see the logged message +.IP 6) 4 +display stats again and observe increment by 1 + +.EX + hadi@noma1:$ tc qdisc add dev eth0 ingress + hadi@noma1:$tc filter add dev eth0 parent ffff: protocol ip prio 5 \\ + u32 match ip protocol 1 0xff flowid 1:1 action simple sdata "Incoming ICMP" + + hadi@noma1:$ sudo tc -s filter ls dev eth0 parent ffff: + filter protocol ip pref 5 u32 + filter protocol ip pref 5 u32 fh 800: ht divisor 1 + filter protocol ip pref 5 u32 fh 800::800 order 2048 key ht 800 bkt 0 flowid 1:1 + match 00010000/00ff0000 at 8 + action order 1: Simple <Incoming ICMP> + index 4 ref 1 bind 1 installed 29 sec used 29 sec + Action statistics: + Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0) + backlog 0b 0p requeues 0 + + + hadi@noma1$ ping -c 1 www.google.ca + PING www.google.ca (74.125.225.120) 56(84) bytes of data. + 64 bytes from ord08s08-in-f24.1e100.net (74.125.225.120): icmp_req=1 ttl=53 time=31.3 ms + + --- www.google.ca ping statistics --- + 1 packets transmitted, 1 received, 0% packet loss, time 0ms + rtt min/avg/max/mdev = 31.316/31.316/31.316/0.000 ms + + hadi@noma1$ dmesg | grep simple + [135354.473951] simple: Incoming ICMP_1 + + hadi@noma1$ sudo tc/tc -s filter ls dev eth0 parent ffff: + filter protocol ip pref 5 u32 + filter protocol ip pref 5 u32 fh 800: ht divisor 1 + filter protocol ip pref 5 u32 fh 800::800 order 2048 key ht 800 bkt 0 flowid 1:1 + match 00010000/00ff0000 at 8 + action order 1: Simple <Incoming ICMP> + index 4 ref 1 bind 1 installed 206 sec used 67 sec + Action statistics: + Sent 84 bytes 1 pkt (dropped 0, overlimits 0 requeues 0) + backlog 0b 0p requeues 0 +.EE +.SH SEE ALSO +.BR tc (8) +.BR tc-actions (8) |