NAME

       tcplife - Trace TCP sessions and summarize lifespan. Uses Linux eBPF/bcc.

SYNOPSIS

       tcplife [-h] [-T] [-t] [-w] [-s] [-p PID] [-D PORTS] [-L PORTS]

DESCRIPTION

       This  tool  traces  TCP  sessions  that open and close while tracing, and prints a line of
       output to summarize each one.  This  includes  the  IP  addresses,  ports,  duration,  and
       throughput  for  the  session.  This  is  useful  for  workload  characterisation and flow
       accounting: identifying what connections are happening, with the bytes transferred.

       This tool works by using kernel dynamic tracing, and will need to be updated if the kernel
       implementation  changes.  Only  TCP  state  changes are traced, so it is expected that the
       overhead of this tool is much lower than typical send/receive tracing.

       Since this uses BPF, only the root user can use this tool.

REQUIREMENTS

       CONFIG_BPF and bcc.

OPTIONS

       -h     Print usage message.

       -s     Comma separated values output (parseable).

       -t     Include a timestamp column (seconds).

       -T     Include a time column (HH:MM:SS).

       -w     Wide column output (fits IPv6 addresses).

       -p PID Trace this process ID only (filtered in-kernel).

       -L PORTS
              Comma-separated list of local ports to trace (filtered in-kernel).

       -D PORTS
              Comma-separated list of destination ports to trace (filtered in-kernel).

EXAMPLES

       Trace all TCP sessions, and summarize lifespan and throughput:
              # tcplife

       Include a timestamp column, and wide column output:
              # tcplife -tw

       Trace PID 181 only:
              # tcplife -p 181

       Trace connections to local ports 80 and 81 only:
              # tcplife -L 80,81

       Trace connections to remote port 80 only:
              # tcplife -D 80

FIELDS

       TIME   Time of the call, in HH:MM:SS format.

       TIME(s)
              Time of the call, in seconds.

       PID    Process ID

       COMM   Process name

       IP     IP address family (4 or 6)

       LADDR  Local IP address.

       DADDR  Remote IP address.

       LPORT  Local port.

       DPORT  Destination port.

       TX_KB  Total transmitted Kbytes.

       RX_KB  Total received Kbytes.

       MS     Lifespan of the session, in milliseconds.

OVERHEAD

       This traces the kernel TCP set state function, which should be called much less often than
       send/receive  tracing,  and  therefore  have  lower  overhead. The overhead of the tool is
       relative to the rate of new TCP sessions: if this is high, over 10,000  per  second,  then
       there  may  be  noticeable  overhead  just  to print out 10k lines of formatted output per
       second.

       You can find out the rate of new TCP sessions  using  "sar  -n  TCP  1",  and  adding  the
       active/s and passive/s columns.

       As  always,  test  and  understand  this tools overhead for your types of workloads before
       production use.

SOURCE

       This is from bcc.

              https://github.com/iovisor/bcc

       Also look in the bcc distribution for a companion _examples.txt  file  containing  example
       usage, output, and commentary for this tool.

OS

       Linux

STABILITY

       Unstable - in development.

AUTHOR

       Brendan Gregg

SEE ALSO

       tcpaccept(8), tcpconnect(8), tcptop(8)