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dropwatch(1) [centos man page]

dropwatch(1)						      General Commands Manual						      dropwatch(1)

NAME
dropwatch - kernel dropped packet monitoring utility SYNOPSIS
dropwatch [-l <method> | list] DESCRIPTION
dropwatch dropwatch is an interactive utility for monitoring and recording packets that are dropped by the kernel OPTIONS
-l <method> | list Select the translation method to use when a drop alert arrives. By default the raw instruction pointer of a drop location is out- put, but by the use of the -l option, we can assign a translation method so that the instruction pointer can be translated into function names. Currently supported lookup methods are: kas - use /proc/kallsyms to lookup instruction pointers to function mappings INTERACTIVE COMMANDS
start Tells the kernel to start reporting dropped packets stop Tells the kernel to discontinue reporting dropped packets exit Exits the dropmonitor program help Displays summary of all commands set alertlimit <value> Sets a triggerpoint to stop monitoring for dropped packets after <value> alerts have been received Neil Horman Mar 2009 dropwatch(1)

Check Out this Related Man Page

PCAP_STATS(3PCAP)														 PCAP_STATS(3PCAP)

NAME
pcap_stats - get capture statistics SYNOPSIS
#include <pcap/pcap.h> int pcap_stats(pcap_t *p, struct pcap_stat *ps); DESCRIPTION
pcap_stats() fills in the struct pcap_stat pointed to by its second argument. The values represent packet statistics from the start of the run to the time of the call. pcap_stats() is supported only on live captures, not on ``savefiles''; no statistics are stored in ``savefiles'', so no statistics are available when reading from a ``savefile''. A struct pcap_stat has the following members: ps_recv number of packets received; ps_drop number of packets dropped because there was no room in the operating system's buffer when they arrived, because packets weren't being read fast enough; ps_ifdrop number of packets dropped by the network interface or its driver. The statistics do not behave the same way on all platforms. ps_recv might count packets whether they passed any filter set with pcap_set- filter(3PCAP) or not, or it might count only packets that pass the filter. It also might, or might not, count packets dropped because there was no room in the operating system's buffer when they arrived. ps_drop is not available on all platforms; it is zero on platforms where it's not available. If packet filtering is done in libpcap, rather than in the operating system, it would count packets that don't pass the filter. Both ps_recv and ps_drop might, or might not, count packets not yet read from the operating system and thus not yet seen by the application. ps_ifdrop might, or might not, be implemented; if it's zero, that might mean that no packets were dropped by the interface, or it might mean that the statistic is unavailable, so it should not be treated as an indication that the interface did not drop any packets. RETURN VALUE
pcap_stats() returns 0 on success and returns -1 if there is an error or if p doesn't support packet statistics. If -1 is returned, pcap_geterr() or pcap_perror() may be called with p as an argument to fetch or display the error text. SEE ALSO
pcap(3PCAP), pcap_geterr(3PCAP) 7 September 2009 PCAP_STATS(3PCAP)

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