1SNMPNETSTAT(1) Net-SNMP SNMPNETSTAT(1)
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6 snmpnetstat - display networking status and configuration information
7 from a network entity via SNMP
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10 snmpnetstat [COMMON OPTIONS] [-Ca] [-Cn] [-Cv] [-Cf address_family]
11 AGENT
12 snmpnetstat [COMMON OPTIONS] [-Cr] [-Cn] [-Cv] [-Cf address_family]
13 AGENT
14 snmpnetstat [COMMON OPTIONS] [-Ci] [-C o | b | d] [-Cn] [-Cv] [-CI
15 interface] [-Cw interval] AGENT
16 snmpnetstat [COMMON OPTIONS] [-Cs[s]] [-Cp protocol] AGENT
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19 The snmpnetstat command symbolically displays the values of various
20 network-related information retrieved from a remote system using the
21 SNMP protocol. There are a number of output formats, depending on the
22 options for the information presented. The first form of the command
23 displays a list of active sockets. The second form presents the values
24 of other network-related information according to the option selected.
25 Using the third form, with an interval specified, snmpnetstat will con‐
26 tinuously display the information regarding packet traffic on the con‐
27 figured network interfaces. The fourth form displays statistics about
28 the named protocol.
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30 snmpnetstat will issue GETBULK requests to query for information if at
31 least protocol version v2 is used.
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33 AGENT identifies a target SNMP agent, which is instrumented to monitor
34 the given objects. At its simplest, the AGENT specification will con‐
35 sist of a hostname or an IPv4 address. In this situation, the command
36 will attempt communication with the agent, using UDP/IPv4 to port 161
37 of the given target host. See snmpcmd(1) for a full list of the possi‐
38 ble formats for AGENT.
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41 The options have the following meaning:
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43 COMMON OPTIONS
44 Please see snmpcmd(1) for a list of possible values for common options
45 as well as their descriptions.
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47 -CL use the legacy SNMP MIB elements, not the modern IP version agnos‐
48 tic tables. snmpnetstat will automatically fall back to the legacy
49 tables if the modern ones are not available.
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51 -Ca With the default display, show the state of all sockets; normally
52 sockets used by server processes are not shown.
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54 -Cf address_family Only show entries for the selected address family
55 (inet, inet6)
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57 -Ci Show the state of all of the network interfaces. The interface
58 display provides a table of cumulative statistics regarding packets
59 transferred, errors, and collisions. The network addresses of the
60 interface and the maximum transmission unit (``mtu'') are also dis‐
61 played.
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63 -Cd Add dropped packets to the interface display.
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65 -Cb Show an extended interface status, giving octets in addition to
66 packets.
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68 -Co Show an abbreviated interface status, giving octets in place of
69 packets. This is useful when enquiring virtual interfaces (such as
70 Frame-Relay circuits) on a router.
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72 -CI interface Show information only about this interface; used with an
73 interval as described below.
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75 -Cn Show network addresses as numbers (normally snmpnetstat interprets
76 addresses and attempts to display them symbolically). This option may
77 be used with any of the display formats.
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79 -Cv Allow long host or service names to break the columnar output.
80 This option may be used with any of the display formats.
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82 -Cp protocol Show statistics about protocol, which is either a well-
83 known name for a protocol or an alias for it. Some protocol names and
84 aliases are listed in the file /etc/protocols. A null response typi‐
85 cally means that there are no interesting numbers to report. The pro‐
86 gram will complain if protocol is unknown or if there is no statistics
87 routine for it.
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89 -Cs Show per-protocol statistics. If this is duplicated (-Css) statis‐
90 tics entries which are zero will be suppressed.
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92 -Cr Show the routing tables.
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94 -CR repeaters For GETBULK requests, repeaters specifies the max-
95 repeaters value to use.
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97 When snmpnetstat is invoked with an interval argument, it displays a
98 running count of statistics related to network interfaces. interval is
99 the number of seconds between reporting of statistics.
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101 The Active Sockets Display (default)
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103 The default display, for active sockets, shows the local and remote
104 addresses, protocol, and the internal state of the protocol. Address
105 formats are of the form ``host.port'' or ``network.port'' if a socket's
106 address specifies a network but no specific host address. When known,
107 the host and network addresses are displayed symbolically according to
108 the databases /etc/hosts and /etc/networks, respectively. If a sym‐
109 bolic name for an address is unknown, or if the -Cn option is speci‐
110 fied, the address is printed numerically, according to the address fam‐
111 ily. For more information regarding the Internet ``dot format,'' refer
112 to inet(3N). Unspecified, or ``wildcard'', addresses and ports appear
113 as ``*''.
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115 The Interface Display
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117 The interface display provides a table of cumulative statistics regard‐
118 ing packets transferred, errors, and col- lisions. The network
119 addresses of the interface and the maximum transmission unit (``mtu'')
120 are also displayed.
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122 The Routing Table Display
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124 The routing table display indicates the available routes and their sta‐
125 tus. Each route consists of a destination host or network and a gate‐
126 way to use in forwarding pack- ets. The flags field shows the state of
127 the route (``U'' if ``up''), whether the route is to a gateway (``G''),
128 whether the route was created dynamically by a redirect (``D''), and
129 whether the route has been modified by a redirect (``M''). Direct
130 routes are created for each interface attached to the local host; the
131 gateway field for such entries shows the address of the outgoing inter-
132 face. The interface entry indicates the network interface utilized for
133 the route.
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135 The Interface Display with an Interval
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137 When snmpnetstat is invoked with an interval argument, it displays a
138 running count of statistics related to network interfaces. This dis‐
139 play consists of a column for the primary interface and a column summa‐
140 rizing information for all interfaces. The primary interface may be
141 replaced with another interface with the -CI option. The first line of
142 each screen of information contains a summary since the system was last
143 rebooted. Subsequent lines of output show values accumulated over the
144 preceding interval.
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146 The Active Sockets Display for a Single Protocol
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148 When a protocol is specified with the -Cp option, the information dis‐
149 played is similar to that in the default display for active sockets,
150 except the display is limited to the given protocol.
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153 Example of using snmpnetstat to display active sockets (default):
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155 % snmpnetstat -v 2c -c public -Ca testhost
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157 Active Internet (tcp) Connections (including servers)
158 Proto Local Address Foreign Address (state)
159 tcp *.echo *.* LISTEN
160 tcp *.discard *.* LISTEN
161 tcp *.daytime *.* LISTEN
162 tcp *.chargen *.* LISTEN
163 tcp *.ftp *.* LISTEN
164 tcp *.telnet *.* LISTEN
165 tcp *.smtp *.* LISTEN
166 ...
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168 Active Internet (udp) Connections
169 Proto Local Address
170 udp *.echo
171 udp *.discard
172 udp *.daytime
173 udp *.chargen
174 udp *.time
175 ...
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177 % snmpnetstat -v 2c -c public -Ci testhost
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179 Name Mtu Network Address Ipkts Ierrs Opkts Oerrs Queue
180 eri0 1500 10.6.9/24 testhost 170548881 245601 687976 0 0
181 lo0 8232 127 localhost 7530982 0 7530982 0 0
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183 Example of using snmpnetstat to show statistics about a specific proto‐
184 col:
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186 % snmpnetstat -v 2c -c public -Cp tcp testhost
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188 Active Internet (tcp) Connections
189 Proto Local Address Foreign Address (state)
190 tcp *.echo *.* LISTEN
191 tcp *.discard *.* LISTEN
192 tcp *.daytime *.* LISTEN
193 tcp *.chargen *.* LISTEN
194 tcp *.ftp *.* LISTEN
195 tcp *.telnet *.* LISTEN
196 tcp *.smtp *.* LISTEN
197 ...
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200 snmpcmd(1), iostat(1), vmstat(1), hosts(5), networks(5), protocols(5),
201 services(5).
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204 The notion of errors is ill-defined.
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208V5.8 04 Nov 2013 SNMPNETSTAT(1)