LNSTAT(8) System Manager's Manual LNSTAT(8)
NAME
lnstat - unified linux network statistics
SYNOPSIS
lnstat [options]
DESCRIPTION
This manual page documents briefly the lnstat command.
lnstat is a generalized and more feature-complete replacement for the
old rtstat program. It is commonly used to periodically print a selec-
tion of statistical values exported by the kernel. In addition to rout-
ing cache statistics, it supports any kind of statistics the linux ker-
nel exports via a file in /proc/net/stat/.
Each file in /proc/net/stat/ contains a header line listing the column
names. These names are used by lnstat as keys for selecting which sta-
tistics to print. For every CPU present in the system, a line follows
which lists the actual values for each column of the file. lnstat sums
these values up (which in fact are counters) before printing them. After
each interval, only the difference to the last value is printed.
Files and columns may be selected by using the -f and -k parameters. By
default, all columns of all files are printed.
OPTIONS
lnstat supports the following options.
-h, --help
Show summary of options.
-V, --version
Show version of program.
-c, --count <count>
Print <count> number of intervals.
-d, --dump
Dump list of available files/keys.
-f, --file <file>
Statistics file to use, may be specified multiple times. By de-
fault all files in /proc/net/stat are scanned.
-i, --interval <intv>
Set interval to 'intv' seconds.
-j, --json
Display results in JSON format
-k, --keys k,k,k,...
Display only keys specified. Each key k is of the form
[file:]key. If <file> is given, the search for the given key is
limited to that file. Otherwise the first file containing the
searched key is being used.
-s, --subject [0-2]
Specify display of subject/header. '0' means no header at all,
'1' prints a header only at start of the program and '2' prints a
header every 20 lines.
-w, --width n,n,n,...
Width for each field.
USAGE EXAMPLES
# lnstat -d
Get a list of supported statistics files.
# lnstat -k arp_cache:entries,rt_cache:in_hit,arp_cache:destroys
Select the specified files and keys.
# lnstat -i 10
Use an interval of 10 seconds.
# lnstat -f ip_conntrack
Use only the specified file for statistics.
# lnstat -s 0
Do not print a header at all.
# lnstat -s 20
Print a header at start and every 20 lines.
# lnstat -c -1 -i 1 -f rt_cache -k entries,in_hit,in_slow_tot
Display statistics for keys entries, in_hit and in_slow_tot of
field rt_cache every second.
FILES
/proc/net/stat/arp_cache, /proc/net/stat/ndisc_cache
Statistics around neighbor cache and ARP. arp_cache is for IPv4,
ndisc_cache is the same for IPv6.
entries Number of entries in the neighbor table.
allocs How many neighbor entries have been allocated.
destroys How many neighbor entries have been removed.
hash_grows How often the neighbor (hash) table was increased.
lookups How many lookups were performed.
hits How many lookups were successful.
res_failed How many neighbor lookups failed.
rcv_probes_mcast How many multicast neighbor solicitations were
received. (IPv6 only.)
rcv_probes_ucast How many unicast neighbor solicitations were re-
ceived. (IPv6 only.)
periodic_gc_runs How many garbage collection runs were executed.
forced_gc_runs How many forced garbage collection runs were exe-
cuted. Happens when adding an entry and the table is too full.
unresolved_discards How many neighbor table entries were dis-
carded due to lookup failure.
table_fulls Number of table overflows. Happens if table is full
and forced GC run (see forced_gc_runs) has failed.
/proc/net/stat/ip_conntrack, /proc/net/stat/nf_conntrack
Conntrack related counters. ip_conntrack is for backwards compat-
ibility with older userspace only and shows the same data as
nf_conntrack.
entries Number of entries in conntrack table.
searched Number of conntrack table lookups performed.
found Number of searched entries which were successful.
new Number of conntrack entries added which were not expected be-
fore.
invalid Number of packets seen which can not be tracked.
ignore Number of packets seen which are already connected to a
conntrack entry.
delete Number of conntrack entries which were removed.
delete_list Number of conntrack entries which were put to dying
list.
insert Number of entries inserted into the list.
insert_failed Number of entries for which list insertion was at-
tempted but failed (happens if the same entry is already
present).
drop Number of packets dropped due to conntrack failure. Either
new conntrack entry allocation failed, or protocol helper dropped
the packet.
early_drop Number of dropped conntrack entries to make room for
new ones, if maximum table size was reached.
icmp_error Number of packets which could not be tracked due to
error situation. This is a subset of invalid.
expect_new Number of conntrack entries added after an expectation
for them was already present.
expect_create Number of expectations added.
expect_delete Number of expectations deleted.
search_restart Number of conntrack table lookups which had to be
restarted due to hashtable resizes.
/proc/net/stat/rt_cache
Routing cache statistics.
entries Number of entries in routing cache.
in_hit Number of route cache hits for incoming packets. Depre-
cated since IP route cache removal, therefore always zero.
in_slow_tot Number of routing cache entries added for input traf-
fic.
in_slow_mc Number of multicast routing cache entries added for
input traffic.
in_no_route Number of input packets for which no routing table
entry was found.
in_brd Number of matched input broadcast packets.
in_martian_dst Number of incoming martian destination packets.
in_martian_src Number of incoming martian source packets.
out_hit Number of route cache hits for outgoing packets. Depre-
cated since IP route cache removal, therefore always zero.
out_slow_tot Number of routing cache entries added for output
traffic.
out_slow_mc Number of multicast routing cache entries added for
output traffic.
gc_total Total number of garbage collection runs. Deprecated
since IP route cache removal, therefore always zero.
gc_ignored Number of ignored garbage collection runs due to mini-
mum GC interval not reached and routing cache not full. Depre-
cated since IP route cache removal, therefore always zero.
gc_goal_miss Number of garbage collector goal misses. Deprecated
since IP route cache removal, therefore always zero.
gc_dst_overflow Number of destination cache overflows. Deprecated
since IP route cache removal, therefore always zero.
in_hlist_search Number of hash table list traversals for input
traffic. Deprecated since IP route cache removal, therefore al-
ways zero.
out_hlist_search Number of hash table list traversals for output
traffic. Deprecated since IP route cache removal, therefore al-
ways zero.
SEE ALSO
ip(8)
AUTHOR
lnstat was written by Harald Welte <laforge@gnumonks.org>.
This manual page was written by Michael Prokop <mika@grml.org> for the
Debian project (but may be used by others).
LNSTAT(8)
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