NAME
hobbitping - Xymon ping tool
SYNOPSIS
hobbitping [--retries=N] [--timeout=N] [IP-adresses]
DESCRIPTION
hobbitping(1) is used for ping testing of the hosts monitored by the
xymon(7) monitoring system. It reads a list of IP adresses from stdin,
and performs a "ping" check to see if these hosts are alive. It is
normally invoked by the bbtest-net(1) utility, which performs all of
the Xymon network tests.
Optionally, if a list of IP-adresses is passed as commandline
arguments, it will ping those IP’s instead of reading them from stdin.
hobbitping only handles IP-adresses, not hostnames.
hobbitping was inspired by the fping(1) tool, but has been written from
scratch to implement a fast ping tester without much of the overhead
found in other such utilities. The output from hobbitping is similar to
that of "fping -Ae".
hobbitping probes multiple systems in parallel, and the runtime is
therefore mostly dependant on the timeout-setting and the number of
retries. With the default options, hobbitping takes approximately 18
seconds to ping all hosts (tested with an input set of 1500 IP
adresses).
SUID-ROOT INSTALLATION REQUIRED
hobbitping needs to be installed with suid-root privileges, since it
requires a "raw socket" to send and receive ICMP Echo (ping) packets.
hobbitping is implemented such that it immediately drops the root
privileges, and only regains them to perform two operations: Obtaining
the raw socket, and optionally binding it to a specific source address.
These operations are performed as root, the rest of the time hobbitping
runs with normal user privileges. Specifically, no user-supplied data
or network data is used while running with root privileges. Therefore
it should be safe to provide hobbitping with the necessary suid-root
privileges.
OPTIONS
--retries=N
Sets the number of retries for hosts that fail to respond to the
initial ping, i.e. the number of ping probes sent in addition to
the initial probe. The default is --retries=2, to ping a host 3
times before concluding that it is not responding.
--timeout=N
Determines the timeout (in seconds) for ping probes. If a host
does not respond within N seconds, it is regarded as
unavailable, unless it responds to one of the retries. The
default is --timeout=5.
--responses=N
hobbitping normally stops pinging a host after receiving a
single response, and uses that to determine the round-trip time.
If the first response takes longer to arrive - e.g. because of
additional network overhead when first determining the route to
the target host - it may skew the round-trip-time reports. You
can then use this option to require N responses, and hobbitping
will calculate the round-trip time as the average of all of
responsetimes.
--max-pps=N
Maximum number of packets per second. This limits the number of
ICMP packets hobbitping will send per second, by enforcing a
brief delay after each packet is sent. The default setting is to
send a maximum of 50 packets per second. Note that increasing
this may cause flooding of the network, and since ICMP packets
can be discarded by routers and other network equipment, this
can cause erratic behaviour with hosts recorded as not
responding when they are in fact OK.
--source=ADDRESS
Use ADDRESS as the source IP address of the ping packets sent.
On multi-homed systems, allows you to select the source IP of
the hosts going out, which might be necessary for ping to work.
--debug
Enable debug output. This prints out all packets sent and
received.
SEE ALSO
xymon(7), bbtest-net(1), fping(1)