===== Test Network ===== ==== Test packet size (MTU) ==== You can check the maximum packet size on network using ping [root@testh]/root# ping -c2 -w 10 -s 1470 nim01 1478 bytes from 172.10.10.10: icmp_seq=2 ttl=64 time=0 ms 45 00 05 c6 c3 8f 00 00 40 01 32 51 ac 15 13 8b * E.......@.2Q.... ac 15 13 8d 00 00 7b be 01 3a 00 03 64 ff 17 2d * ......{..:..d..- 00 0b 8c c0 00 84 01 3a 00 01 02 03 04 05 06 07 * .......:........ 08 09 0a 0b 0c 0d 0e 0f 10 11 12 13 14 15 16 17 * ................ 18 19 1a 1b 1c 1d 1e 1f 20 21 22 23 24 25 26 27 * ........ !"#$%&' 28 29 2a 2b 2c 2d 2e 2f 30 31 32 33 34 35 36 37 * ()*+,-./01234567 38 39 3a 3b 3c 3d 3e 3f 40 41 42 43 44 45 46 47 * 89:;<=>?@ABCDEFG 48 49 4a 4b 4c 4d 4e 4f 50 51 52 53 54 55 56 57 * HIJKLMNOPQRSTUVW 58 59 5a 5b 5c 5d 5e 5f 60 61 62 63 64 65 66 67 * XYZ[\]^_`abcdefg 68 69 6a 6b 6c 6d 6e 6f 70 71 72 73 74 75 76 77 * hijklmnopqrstuvw 78 79 7a 7b 7c 7d 7e 7f 80 81 82 83 84 85 86 87 * xyz{|}~......... 88 89 8a 8b 8c 8d 8e 8f 90 91 92 93 94 95 96 97 * ................ 98 99 9a 9b 9c 9d 9e 9f a0 a1 a2 a3 a4 a5 a6 a7 * ................ ... If packet size are to high, you 'll have a packet lost 100% [root@testh]/root# ping -c2 -w 10 -D -s 9000 nim01 PING nim01.lu (172.10.10.10): 1500 data bytes --- nim01.lu ping statistics --- 2 packets transmitted, 0 packets received, 100% packet loss Generate network trafic and check the packet size, here packet 1500, on NFS [root@testh]/root# tcpdump -i en1 -vvv host myserver.lu 16:33:44.209433 IP (tos 0x0, ttl 60, id 20437, offset 0, flags [none], proto TCP (6), length 1500) testh.lu.42305 > myserver.lu.shilp: Flags [.], cksum 0x0000 (incorrect -> 0xa6bb), seq 495870232:495871680, ack 4016785, win 65535, options [nop,nop,TS val 1698414524 ecr 4145383147], length 1448: NFS request xid 0 0 null 16:33:44.209438 IP (tos 0x0, ttl 60, id 20438, offset 0, flags [none], proto TCP (6), length 1500) testh.lu.42305 > myserver.lu.shilp: Flags [.], cksum 0x0000 (incorrect -> 0xa113), seq 495871680:495873128, ack 4016785, win 65535, options [nop,nop,TS val 1698414524 ecr 4145383147], length 1448: NFS request xid 0 0 null 16:33:44.209445 IP (tos 0x0, ttl 60, id 20439, offset 0, flags [none], proto TCP (6), length 1500) testh.lu.42305 > myserver.lu.shilp: Flags [.], cksum 0x0000 (incorrect -> 0x9b6b), seq 495873128:495874576, ack 4016785, win 65535, options [nop,nop,TS val 1698414524 ecr 4145383147], length 1448: NFS request xid 0 0 null 29300 packets captured 462059 packets received by filter 432674 packets dropped by kernel ==== Reset count in netstat ==== To clear some statistics for the adapters netstat -Zv Or entstat -r entX ==== Using iperf ==== Iperf is a free tool available on linux, and AIX (perzl.org), also available for Windows You must first start the iperf server (-s) to listen for communication, and the start a client (-c) which generates traffic. In my case nimbcp is the server, and nimprod the client. You can test for example latency (Jitter) on network using UDP (-u) protocol: root@nimbcp - /root > iperf -s -P 5 -i 1 -u ------------------------------------------------------------ Server listening on UDP port 5001 Receiving 1470 byte datagrams UDP buffer size: 640 KByte (default) ------------------------------------------------------------ ..... [ ID] Interval Transfer Bandwidth Jitter Lost/Total Datagrams [ 3] 0.0- 1.0 sec 129 KBytes 1.06 Mbits/sec 0.116 ms 0/ 89 (0%) [ 4] 0.0- 1.0 sec 126 KBytes 1.03 Mbits/sec 0.128 ms 1/ 89 (1.1%) [ 5] 0.0- 1.0 sec 128 KBytes 1.05 Mbits/sec 0.113 ms 1/ 89 (1.1%) root@nimprod - /root > iperf -r -c nimbcp -P 5 -i 1 -u WARNING: option -r is not valid for server mode ------------------------------------------------------------ Client connecting to nimbcp, UDP port 5001 Sending 1470 byte datagrams UDP buffer size: 64.0 KByte (default) ------------------------------------------------------------ ... [ ID] Interval Transfer Bandwidth [ 7] 0.0- 1.0 sec 129 KBytes 1.06 Mbits/sec [ 3] 0.0- 1.0 sec 129 KBytes 1.06 Mbits/sec [ 4] 0.0- 1.0 sec 129 KBytes 1.06 Mbits/sec [ 5] 0.0- 1.0 sec 129 KBytes 1.06 Mbits/sec [ 6] 0.0- 1.0 sec 129 KBytes 1.06 Mbits/sec [SUM] 0.0- 1.0 sec 646 KBytes 5.29 Mbits/sec You can test for example TCP throughput on network on 5 parallel connections: root@nimbcp - /root > iperf -s -P 5 -i 1 ------------------------------------------------------------ Server listening on TCP port 5001 TCP window size: 256 KByte (default) ------------------------------------------------------------ .... [ ID] Interval Transfer Bandwidth [ 4] 0.0- 1.0 sec 33.9 MBytes 284 Mbits/sec [ 5] 0.0- 1.0 sec 27.7 MBytes 232 Mbits/sec [ 6] 0.0- 1.0 sec 14.2 MBytes 119 Mbits/sec [ 7] 0.0- 1.0 sec 22.3 MBytes 187 Mbits/sec [ 8] 0.0- 1.0 sec 7.43 MBytes 62.3 Mbits/sec [SUM] 0.0- 1.0 sec 105 MBytes 885 Mbits/sec root@nimprod - /root > iperf -r -c nimbcp -P 5 -i 1 WARNING: option -r is not valid for server mode ------------------------------------------------------------ Client connecting to nimbcp, TCP port 5001 TCP window size: 256 KByte (default) ------------------------------------------------------------ .... [ ID] Interval Transfer Bandwidth [ 3] 0.0- 1.0 sec 34.2 MBytes 287 Mbits/sec [ 4] 0.0- 1.0 sec 28.0 MBytes 235 Mbits/sec [ 6] 0.0- 1.0 sec 22.8 MBytes 191 Mbits/sec [ 5] 0.0- 1.0 sec 14.4 MBytes 121 Mbits/sec [ 7] 0.0- 1.0 sec 7.62 MBytes 64.0 Mbits/sec [SUM] 0.0- 1.0 sec 107 MBytes 898 Mbits/sec ==== Using ftp ==== Network theoretical throughput: ^^speed bit/s^throughput Mbyte/s^throughput Gbyte/s^ ||100 Mbps|12,5MB/s|45 GB/h| ||1 Gbps|125 MB/s|450 GB/h| ||10 Gbps|1,25 GB/s|4500 GB/h| manu@mypc:/tmp> ftp 10.0.10.21 Connected to 10.0.10.21. 220 aix01 FTP server (Version 4.2 Tue Feb 19 19:37:47 CST 2013) ready. Name (10.0.102.21:manu): root 331 Password required for root. Password: 230-Last login: Tue Sep 15 16:09:42 CDT 2015 on /dev/pts/0 from 10.0.11.37 230 User root logged in. Remote system type is UNIX. Using binary mode to transfer files. ftp> cd /tmp 250 CWD command successful. ftp> bin 200 Type set to I. ftp> put "| dd if=/dev/zero bs=32k count=10000" /dev/null local: | dd if=/dev/zero bs=32k count=10000 remote: /dev/null 229 Entering Extended Passive Mode (|||32789|) 150 Opening data connection for /dev/null. 10000+0 records in 10000+0 records out 327680000 bytes (328 MB) copied, 27,8874 s, 11,8 MB/s 226 Transfer complete. 327680000 bytes sent in 00:27 (11.20 MiB/s) ftp> **Remark** As ftp is a single threat process, you have to run multiples sessions in parallel. create a file .netrc machine testftp login root password root macdef init put "|dd if=/dev/zero bs=1M count=1000" /dev/null bye # chmod 400 .netrc # for i in 1 2 3 4 5 6 7 8 do ftp testftp | grep seconds & done