X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=src%2Fmans%2Foping.pod;h=a2307fe9b79a735e2a22d094b428fef1fd91f2b6;hb=a6739449f931f17e44d468c5edd083b2487bcfdf;hp=b495a893e09d37ca66d948ff60e60e6b1ebe0fde;hpb=e3514c7ec3d8d41635a0e37661d8783adcfb6934;p=liboping.git diff --git a/src/mans/oping.pod b/src/mans/oping.pod index b495a89..a2307fe 100644 --- a/src/mans/oping.pod +++ b/src/mans/oping.pod @@ -66,10 +66,18 @@ Set the outgoing network device to use. Instead of specifying hostnames on the command line, read them from I. If I is B<->, read from C. -If the real user ID (as returned by L) and the effective user ID (as +If I is installed with the SetUID-bit, it will set the effective UID to +the real UID before opening the file. In the special (but common) case that +I is owned by the super-user (UIDE0), this means that privileges +are temporarily dropped before opening the file, in order to prevent users from +reading arbitrary files on the system. + +If your system doesn't provide I (this was an optional +feature before POSIXE2001), the behavior is different because it is not +possible to I drop privileges. The alternative behavior is: If the +real user ID (as returned by L) and the effective user ID (as returned by L) differ, the only argument allowed for this option is -"-" (i.Ee. standard input). This is meant to avoid security issues when -I is installed with the SUID-bit. +"-" (i.e. standard input). =item B<-Q> I @@ -78,7 +86,7 @@ somewhat tricky option, since the meaning of the bits in the IPv4 header has been revised several times. The currently recommended method is I which is used in -IPv6 headers as well. There are shortcuts for 13Epredefined +IPv6 headers as well. There are shortcuts for various predefined I (PHBs): =over 4 @@ -93,6 +101,13 @@ Selects the I (EF) per-hop behavior, as defined in I3246>. This PHB is characterised by low delay, low loss and low jitter, i.e. high priority traffic. +=item B + +Selects the I (VA) per-hop behavior, as defined in +I5865>. This traffic class is meant for I (VoIP) +traffic which uses I (CAC) for reserving network +capacity. + =item BII

Selects one of 12Edifferentiated services code points (DSCPs), which are @@ -141,6 +156,99 @@ decimal number (0-255), a hexadecimal number (0x00-0xff) or an octal number (00-0377) using the usual "0x" and "0" prefixes for hexadecimal and octal respectively. +The printed lines will contain information about the QoS field of received +packets if either a non-standard QoS setting was used on outgoing packets or if +the QoS byte of incoming packets is not zero. In other words, the QoS +information is omitted if both, the outgoing and the incoming QoS bytes are +zero. The received byte is always interpreted as +I (DSCP) and +I (ECN), even if the deprecated +I (ToS) aliases were used to specify the bits of outgoing +packets. + +=item B<-u>|B<-U> + +I B<-u> forces UTF-8 output, B<-U> disables UTF-8 output. If +neither is given, the codeset is automatically determined from the locale. + +=item B<-g> B|B|B|B + +I Selects the graph to display. + +=over 4 + +=item B + +Do not show a graph. + +=item B + +Show a graph with time on the x-axis in a round-robin fashion, i.e. continue on +the left if the right edge is reached. The y-axis shows the round-trip time. +This is the default. + +=item B + +Show a I where the x-axis, i.e. the width of the window, is the +round-trip time. The entire width of the window it the ping interval, set with +the B<-i> option. + +The box is sized so it contains 50% of the replies. The vertical line shows the +median. The whiskers are sized to contain 95% of the replies -- 2.5% below the +whiskers and 2.5% above. + + |----------[#####|##########]--------------------------------------------| + ^ ^ ^ ^ ^ + 2.75% 25% 50% 75% 97.5% + +=item B + +Show a I of the round-trip times. The width of the window is taken +as round-trip time from 0ms on the left to the I (the B<-i> option, +default 1000ms) on the right. + +The height of the graph is scaled so that the most-used buckets vertically fills +the line. The buckets are colored green up to and including the median, yellow +up to and including the 95th percentile and red for the remainder. + +In addition, the histogram is colored, if supported by the terminal. The green +bars include the median (50% of responses), yellow bars include the 95th +percentile and outliers are colored red. + +=back + +=item B<-P> I + +Configures the latency percentile to report. I must be a number +between zero and 100, exclusively in both cases. In general, defaults to B<95>. +If B<-c> is given and a number less than 20, this would be the same as the +maximum. In this case the default is chosen so that it excludes the maximum, +e.g. if B<-cE5> is given, the default is I<80>. + +The calculated percentile has roughly millisecond precision. If precision is of +importance, read on for a more detailed explanation. In order to calculate the +percentile without keeping all replies in memory, I divides the +I (the B<-i> option) in 1000 "buckets". Each bucket counts the number +of packets received in the represented time. That means that the precision +decreases if the interval is increased, because each bucket represents a larger +(fraction of the) response time. The code looks for the first bucket +representing at least I responses and returns the upper-bound latency +represented by that bucket. Since the represented percentage may be larger than +the configured percentile, this algorithm I the actual percentile +by at most 1000th of I. + +=item B<-Z> I + +If any hosts have a drop rate higher than I, where I is a +number between zero and 100 inclusively, exit with a non-zero exit status. +Since it is not possible to have a higher drop rate than 100%, passing this +limit will effectively disable the feature (the default). Setting the option to +zero means that the exit status will only be zero if I replies for I +hosts have been received. + +The exit status will indicate the number of hosts with more than I +packets lost, up to a number of 255 failing hosts. + =back =head1 COLORS @@ -150,13 +258,10 @@ If supported by the terminal, I will highlight the round-trip times the "expected" range, yellow marks moderately unusual times and times that differ a lot from the expected value are printed in red. -The information used to categorize round-trip times is the I -round-trip time and the I. RTTs that differ from the -average by less than the standard deviation are considered to be "normal" and -are printed in green. Times that differ from the average more than the standard -deviation but less than twice the standard deviation are considered "moderately -unusual" and are printed in yellow. Times differing more than twice the -standard deviation from the average are considered to be "unusual" and are +The information used to categorize round-trip times is the I. RTTs +in the 80th percentile are considered to be "normal" and are printed in green. +RTTs within the 95th percentile are considered "moderately unusual" and are +printed in yellow. RTTs above that are considered to be "unusual" and are printed in red. =head1 SEE ALSO @@ -165,7 +270,7 @@ L, L, L =head1 AUTHOR -liboping is written by Florian octo Forster Eocto at verplant.orgE. +liboping is written by Florian "octo" Forster Eff at octo.itE. Its homepage can be found at L. -(c) 2005-2010 by Florian octo Forster. +Copyright (c) 2005-2011 by Florian "octo" Forster.