TCPDUMP AND TCPTRACE INSTALL TCPTRACE UBUNTU

Tcpdump And Tcptrace Install Tcptrace Ubuntu

Searching on rpmfind.net I found the one matching my needs, tcptrack for CentOS. I use rpm for RHEL 4.How to install tcptrace ubuntu package on Ubuntu 20.04/Ubuntu. Tcptrace is a tool for analyzing and reporting on tcpdump (or other libpcap) dump files.TCPdump is a network analyzer utility that can monitor and log, TCP/IP traffic passing through the network and the device from which it is executed. TCPdump is open-source and it’s freely available under the BSD license.

It can take as input the files produced by several popular packet-capture programs, including tcpdump, snoop, etherpeek, HP Net Metrix, and WinDump. Tcptrace can produce several different types of output containing information on each connection seen, such as elapsed time, bytes and segments sent. If you are using an RHEL operating system there is a good chance that TCPdump is already installed on your system, so first, run the following command (or any TCPdump command) to check if it is already installed: tcpdump -DTool for analyzing tcpdump output. Tcptrace is a tool for analyzing and reporting on tcpdump (or other libpcap) dump files. Tcptrack also has a filtering feature, it uses the pcap filtering standard (its identic with the one used in tcpdump).

How do we know where latency comes from when there is a disparity in reported I/O latency on the I/O subsystem and that of the latency reported on the client box requesting the I/O.For example if I have an Oracle database requesting I/O and Oracle says an 8Kb request takes 50 ms yet the I/O storage subsystem says 8Kb I/Os are taking 1ms (averages) , then where does the 49 extra ms come from?When the I/O subsystem is connected to Oracle via NFS then there are a lot of layers that could be causing the extra latency.Where does the difference in latency come from between NFS Server and Oracle’s timing of pread?One strategy is to take tcp traces on NFS server and NFS client (the Oracle Host) at the same time, during a period of load that shows the disparity.The two trace files can then be analyzed to show latency at each side and the delta of latency between packets found in both tracesParsing script is ( thanks to Matt Amdur from Delphix for the core code)The script requires access to tethereal command which comes with the wireshark install on LINUX: yum install wireshark Example situationFor example in the following table stats were collected on the NFS server (running Open Solaris) with DTrace and on the Oracle database using oramon.sh. Graph data can be created for throughput, RTT, tcpdump - command-line network traffic analyzer. This program allows you to dump the traffic on a network. Tcpdump is able to examine IPv4, ICMPv4, IPv6, ICMPv6, UDP, TCP, SNMP, AFS BGP, RIP, PIM, DVMRP, IGMP, SMB, OSPF, NFS and many other packet types. It can be used to print out the headers of packets on a network interface, filter packets. 2 Agenda Introduc)on TCPDump Isolate & Capture Traffic TCPTrace Analyze.

-o : output file, give “.cap” extension to be recognized automatically by wiresharkNFS client host is the IP at the end of the command lineLinux (linux client example) tcpdump -s 512 host 172.16.100.87 -w nfs_client.cap The traces will be large, so run them for 20 second for example, to limit the size.TCP dumps can be collected on Linux with tcpdump or on Solaris with snoop:NFS server (Solaris NFS server example) snoop -q -d aggr0 -s 512 -o nfs_server.cap 172.16.100.102 During this period of latency discrepancy collect TCP traces. Setup problem situationFirst, set up a situation where there is a load running on the database and there is a discrepancy between latency on NFS server and as seen by Oracle. Where is the latency coming from? Is it a problem on the NFS server, the NFS client or the network? How do we find out? One strategy is to collect TCP dumps on the NFS client and NFS server and compare them.

In one case the NFS client and database host was Open Solaris and in the other case it was LINUX. The database files were mounted via NFS from the NFS server. /parsetcp.pl nfs_server.cap nfs_client.cap= RAW DATA = MATCHED DATA =Processed 14010 packets (Matched: 11964 Missed: 2046)Processed 5806 packets (Matched: 4391 Missed: 1415)The script will find the average latency for reads and writes on both ends and then try to match the packets found both at the client and server and report the average latency for reads and writes on the packets that match.In the above output the read time on on the NFS client receiving end is on par with what is seen on NFS server.Thus if the receive time on the NFS client host is on par with the NFS server and Oracle latency is much greater than the receive time, then there looks to be some issue on the NFS client host machine such as heavy memory paging that would cause the latency seen by Oracle to be much higher than that seen by the tcp traces.In the following 2 examples a swingbench load was run on the Oracle database on the NFS client.

In other cases where there has been more I/O between the NFS server and client and/or the transfer sizes were higher (like 1M) then the impact of TCP tracing has eclipsed the latency disparity being investigated and tcp tracing would not have been appropriate investigation path.Kyle -> 172.16.100.92 drops: 0 TCP D=50461 S=22 Push Ack=2424998673 Seq=3990657488 Len=84 Win=49640172.16.100.92 -> kyle drops: 0 TCP D=22 S=50461 Ack=3990657572 Seq=2424998673 Len=0 Win=254172.16.100.147 -> (broadcast) drops: 0 ARP C Who is 172.16.100.115, 172.16.100.115 ?172.16.100.68 -> (broadcast) drops: 0 ARP C Who is 172.16.100.115, 172.16.100.115 ?172.16.100.68 -> (broadcast) drops: 0 ARP C Who is 172.16.100. In the above cases with and without tcp tracing enabled showed no more than 1ms of difference and the latency being investigated was an order of magnitude greater. The solution was to raise sunrpc.tcp_slot_table_entries = 128.The tcpdump.pl script didn’t find the answers but it did identify which side of the connection was at fault and it would identify if the network itself was the problem.One thing to keep in mind is that snoop and tcpdump can be resource intensive and may introduce a major amount of latency.

Install Tcpdump And Tcptrace