|  |  | 
|  |  | 
|  | HOWTO for the linux packet generator | 
|  | ------------------------------------ | 
|  |  | 
|  | Date: 041221 | 
|  |  | 
|  | Enable CONFIG_NET_PKTGEN to compile and build pktgen.o either in kernel | 
|  | or as module. Module is preferred. insmod pktgen if needed. Once running | 
|  | pktgen creates a thread on each CPU where each thread has affinty it's CPU. | 
|  | Monitoring and controlling is done via /proc. Easiest to select a suitable | 
|  | a sample script and configure. | 
|  |  | 
|  | On a dual CPU: | 
|  |  | 
|  | ps aux | grep pkt | 
|  | root       129  0.3  0.0     0    0 ?        SW    2003 523:20 [pktgen/0] | 
|  | root       130  0.3  0.0     0    0 ?        SW    2003 509:50 [pktgen/1] | 
|  |  | 
|  |  | 
|  | For montoring and control pktgen creates: | 
|  | /proc/net/pktgen/pgctrl | 
|  | /proc/net/pktgen/kpktgend_X | 
|  | /proc/net/pktgen/ethX | 
|  |  | 
|  |  | 
|  | Viewing threads | 
|  | =============== | 
|  | /proc/net/pktgen/kpktgend_0 | 
|  | Name: kpktgend_0  max_before_softirq: 10000 | 
|  | Running: | 
|  | Stopped: eth1 | 
|  | Result: OK: max_before_softirq=10000 | 
|  |  | 
|  | Most important the devices assigend to thread. Note! A device can only belong | 
|  | to one thread. | 
|  |  | 
|  |  | 
|  | Viewing devices | 
|  | =============== | 
|  |  | 
|  | Parm section holds configured info. Current hold running stats. | 
|  | Result is printed after run or after interruption. Example: | 
|  |  | 
|  | /proc/net/pktgen/eth1 | 
|  |  | 
|  | Params: count 10000000  min_pkt_size: 60  max_pkt_size: 60 | 
|  | frags: 0  delay: 0  clone_skb: 1000000  ifname: eth1 | 
|  | flows: 0 flowlen: 0 | 
|  | dst_min: 10.10.11.2  dst_max: | 
|  | src_min:   src_max: | 
|  | src_mac: 00:00:00:00:00:00  dst_mac: 00:04:23:AC:FD:82 | 
|  | udp_src_min: 9  udp_src_max: 9  udp_dst_min: 9  udp_dst_max: 9 | 
|  | src_mac_count: 0  dst_mac_count: 0 | 
|  | Flags: | 
|  | Current: | 
|  | pkts-sofar: 10000000  errors: 39664 | 
|  | started: 1103053986245187us  stopped: 1103053999346329us idle: 880401us | 
|  | seq_num: 10000011  cur_dst_mac_offset: 0  cur_src_mac_offset: 0 | 
|  | cur_saddr: 0x10a0a0a  cur_daddr: 0x20b0a0a | 
|  | cur_udp_dst: 9  cur_udp_src: 9 | 
|  | flows: 0 | 
|  | Result: OK: 13101142(c12220741+d880401) usec, 10000000 (60byte,0frags) | 
|  | 763292pps 390Mb/sec (390805504bps) errors: 39664 | 
|  |  | 
|  | Confguring threads and devices | 
|  | ============================== | 
|  | This is done via the /proc interface easiest done via pgset in the scripts | 
|  |  | 
|  | Examples: | 
|  |  | 
|  | pgset "clone_skb 1"     sets the number of copies of the same packet | 
|  | pgset "clone_skb 0"     use single SKB for all transmits | 
|  | pgset "pkt_size 9014"   sets packet size to 9014 | 
|  | pgset "frags 5"         packet will consist of 5 fragments | 
|  | pgset "count 200000"    sets number of packets to send, set to zero | 
|  | for continious sends untill explicitl stopped. | 
|  |  | 
|  | pgset "delay 5000"      adds delay to hard_start_xmit(). nanoseconds | 
|  |  | 
|  | pgset "dst 10.0.0.1"    sets IP destination address | 
|  | (BEWARE! This generator is very aggressive!) | 
|  |  | 
|  | pgset "dst_min 10.0.0.1"            Same as dst | 
|  | pgset "dst_max 10.0.0.254"          Set the maximum destination IP. | 
|  | pgset "src_min 10.0.0.1"            Set the minimum (or only) source IP. | 
|  | pgset "src_max 10.0.0.254"          Set the maximum source IP. | 
|  | pgset "dst6 fec0::1"     IPV6 destination address | 
|  | pgset "src6 fec0::2"     IPV6 source address | 
|  | pgset "dstmac 00:00:00:00:00:00"    sets MAC destination address | 
|  | pgset "srcmac 00:00:00:00:00:00"    sets MAC source address | 
|  |  | 
|  | pgset "src_mac_count 1" Sets the number of MACs we'll range through. | 
|  | The 'minimum' MAC is what you set with srcmac. | 
|  |  | 
|  | pgset "dst_mac_count 1" Sets the number of MACs we'll range through. | 
|  | The 'minimum' MAC is what you set with dstmac. | 
|  |  | 
|  | pgset "flag [name]"     Set a flag to determine behaviour.  Current flags | 
|  | are: IPSRC_RND #IP Source is random (between min/max), | 
|  | IPDST_RND, UDPSRC_RND, | 
|  | UDPDST_RND, MACSRC_RND, MACDST_RND | 
|  |  | 
|  | pgset "udp_src_min 9"   set UDP source port min, If < udp_src_max, then | 
|  | cycle through the port range. | 
|  |  | 
|  | pgset "udp_src_max 9"   set UDP source port max. | 
|  | pgset "udp_dst_min 9"   set UDP destination port min, If < udp_dst_max, then | 
|  | cycle through the port range. | 
|  | pgset "udp_dst_max 9"   set UDP destination port max. | 
|  |  | 
|  | pgset stop    	          aborts injection. Also, ^C aborts generator. | 
|  |  | 
|  |  | 
|  | Example scripts | 
|  | =============== | 
|  |  | 
|  | A collection of small tutorial scripts for pktgen is in expamples dir. | 
|  |  | 
|  | pktgen.conf-1-1                  # 1 CPU 1 dev | 
|  | pktgen.conf-1-2                  # 1 CPU 2 dev | 
|  | pktgen.conf-2-1                  # 2 CPU's 1 dev | 
|  | pktgen.conf-2-2                  # 2 CPU's 2 dev | 
|  | pktgen.conf-1-1-rdos             # 1 CPU 1 dev w. route DoS | 
|  | pktgen.conf-1-1-ip6              # 1 CPU 1 dev ipv6 | 
|  | pktgen.conf-1-1-ip6-rdos         # 1 CPU 1 dev ipv6  w. route DoS | 
|  | pktgen.conf-1-1-flows            # 1 CPU 1 dev multiple flows. | 
|  |  | 
|  | Run in shell: ./pktgen.conf-X-Y It does all the setup including sending. | 
|  |  | 
|  |  | 
|  | Interrupt affinity | 
|  | =================== | 
|  | Note when adding devices to a specific CPU there good idea to also assign | 
|  | /proc/irq/XX/smp_affinity so the TX-interrupts gets bound to the same CPU. | 
|  | as this reduces cache bouncing when freeing skb's. | 
|  |  | 
|  |  | 
|  | Current commands and configuration options | 
|  | ========================================== | 
|  |  | 
|  | ** Pgcontrol commands: | 
|  |  | 
|  | start | 
|  | stop | 
|  |  | 
|  | ** Thread commands: | 
|  |  | 
|  | add_device | 
|  | rem_device_all | 
|  | max_before_softirq | 
|  |  | 
|  |  | 
|  | ** Device commands: | 
|  |  | 
|  | count | 
|  | clone_skb | 
|  | debug | 
|  |  | 
|  | frags | 
|  | delay | 
|  |  | 
|  | src_mac_count | 
|  | dst_mac_count | 
|  |  | 
|  | pkt_size | 
|  | min_pkt_size | 
|  | max_pkt_size | 
|  |  | 
|  | udp_src_min | 
|  | udp_src_max | 
|  |  | 
|  | udp_dst_min | 
|  | udp_dst_max | 
|  |  | 
|  | flag | 
|  | IPSRC_RND | 
|  | TXSIZE_RND | 
|  | IPDST_RND | 
|  | UDPSRC_RND | 
|  | UDPDST_RND | 
|  | MACSRC_RND | 
|  | MACDST_RND | 
|  |  | 
|  | dst_min | 
|  | dst_max | 
|  |  | 
|  | src_min | 
|  | src_max | 
|  |  | 
|  | dst_mac | 
|  | src_mac | 
|  |  | 
|  | clear_counters | 
|  |  | 
|  | dst6 | 
|  | src6 | 
|  |  | 
|  | flows | 
|  | flowlen | 
|  |  | 
|  | References: | 
|  | ftp://robur.slu.se/pub/Linux/net-development/pktgen-testing/ | 
|  | ftp://robur.slu.se/pub/Linux/net-development/pktgen-testing/examples/ | 
|  |  | 
|  | Paper from Linux-Kongress in Erlangen 2004. | 
|  | ftp://robur.slu.se/pub/Linux/net-development/pktgen-testing/pktgen_paper.pdf | 
|  |  | 
|  | Thanks to: | 
|  | Grant Grundler for testing on IA-64 and parisc, Harald Welte,  Lennert Buytenhek | 
|  | Stephen Hemminger, Andi Kleen, Dave Miller and many others. | 
|  |  | 
|  |  | 
|  | Good luck with the linux net-development. |