1SNMPNETSTAT(1) Net-SNMP SNMPNETSTAT(1)
2
6 snmpnetstat - display networking status and configuration information
7 from a network entity via SNMP
8
10 snmpnetstat [common options] [-Ca] [-Cn] AGENT
11 snmpnetstat [common options] [-Ci] [-Co] [-Cr] [-Cn] [-Cs] AGENT
12 snmpnetstat [common options] [-Ci] [-Cn] [-CI interface] AGENT [inter‐
13 val]
14 snmpnetstat [common options] [-Ca] [-Cn] [-Cs] [-CP protocol] AGENT
15
17 The snmpnetstat command symbolically displays the values of various
18 network-related information retrieved from a remote system using the
19 SNMP protocol. There are a number of output formats, depending on the
20 options for the information presented. The first form of the command
21 displays a list of active sockets. The second form presents the values
22 of other network-related information according to the option selected.
23 Using the third form, with an interval specified, snmpnetstat will con‐
24 tinuously display the information regarding packet traffic on the con‐
25 figured network interfaces. The fourth form displays statistics about
26 the named protocol.
27 AGENT identifies a target SNMP agent, which is instrumented to monitor
29 the given objects. At its simplest, the AGENT specification will con‐
30 sist of a hostname or an IPv4 address. In this situation, the command
31 will attempt communication with the agent, using UDP/IPv4 to port 161
32 of the given target host. See snmpcmd(1) for a full list of the possi‐
33 ble formats for AGENT.
34
36 The options have the following meaning:
37 common options
39 Please see snmpcmd(1) for a list of possible values for common options
40 as well as their descriptions.
41 -Ca With the default display, show the state of all sockets; normally
43 sockets used by server processes are not shown.
44 -Ci Show the state of all of the network interfaces. The interface
46 display provides a table of cumulative statistics regarding packets
47 transferred, errors, and collisions. The network addresses of the
48 interface and the maximum transmission unit (``mtu'') are also dis‐
49 played.
50 -Co Show an abbreviated interface status, giving octets in place of
52 packets. This is useful when enquiring virtual interfaces (such as
53 Frame-Relay circuits) on a router.
54 -CI interface Show information only about this interface; used with an
56 interval as described below.
57 -Cn Show network addresses as numbers (normally snmpnetstat interprets
59 addresses and attempts to display them symbolically). This option may
60 be used with any of the display formats.
61 -CP protocol Show statistics about protocol, which is either a well-
63 known name for a protocol or an alias for it. Some protocol names and
64 aliases are listed in the file /etc/protocols. A null response typi‐
65 cally means that there are no interesting numbers to report. The pro‐
66 gram will complain if protocol is unknown or if there is no statistics
67 routine for it.
68 -Cs Show per-protocol statistics. When used with the -Cr option, show
70 routing statistics instead.
71 -Cr Show the routing tables. When -Cs is also present, show per-proto‐
73 col routing statistics instead of the routing tables.
74 When snmpnetstat is invoked with an interval argument, it displays a
76 running count of statistics related to network interfaces. interval
77 is the number of seconds between reporting of statistics.
78 The Active Sockets Display (default)
80 The default display, for active sockets, shows the local and remote
82 addresses, protocol, and the internal state of the protocol.
83 Address formats are of the form ``host.port'' or ``net‐
84 work.port'' if a socket's address specifies a network but no spe‐
85 cific host address. When known, the host and network addresses are
86 displayed symbolically according to the data bases /etc/hosts and
87 /etc/networks, respectively. If a symbolic name for an address is
88 unknown, or if the -Cn option is specified, the address is printed
89 numerically, according to the address family. For more information
90 regarding the Internet ``dot format,'' refer to inet(3N). Unspeci‐
91 fied, or ``wildcard'', addresses and ports appear as ``*''.
92 The Interface Display
94 The interface display provides a table of cumulative statistics
96 regarding packets transferred, errors, and col- lisions. The network
97 addresses of the interface and the maximum transmission unit (``mtu'')
98 are also displayed.
99 The Routing Table Display
101 The routing table display indicates the available routes and their
103 status. Each route consists of a destination host or network and a
104 gateway to use in forwarding pack- ets. The flags field shows the
105 state of the route (``U'' if ``up''), whether the route is to a
106 gateway (``G''), whether the route was created dynamically by a re‐
107 direct (``D''), and whether the route has been modified by a redi‐
108 rect (``M''). Direct routes are created for each interface
109 attached to the local host; the gateway field for such entries
110 shows the address of the outgoing inter- face. The interface entry
111 indicates the network interface utilized for the route.
112 The Interface Display with an Interval
114 When snmpnetstat is invoked with an interval argument, it displays a
116 running count of statistics related to network interfaces. This
117 display consists of a column for the primary interface and a column
118 summarizing information for all interfaces. The primary interface
119 may be replaced with another interface with the -CI option. The first
120 line of each screen of information contains a summary since the system
121 was last rebooted. Subsequent lines of output show values accumulated
122 over the preceding interval.
123 The Active Sockets Display for a Single Protocol
125 When a protocol is specified with the -CP option, the information dis‐
127 played is similar to that in the default display for active sockets,
128 except the display is limited to the given protocol.
129
131 Example of using snmpnetstat to display active sockets (default):
132 % snmpnetstat -v 2c -c public -Ca testhost
134 Active Internet (tcp) Connections (including servers)
136 Proto Local Address Foreign Address (state)
137 tcp *.echo *.* LISTEN
138 tcp *.discard *.* LISTEN
139 tcp *.daytime *.* LISTEN
140 tcp *.chargen *.* LISTEN
141 tcp *.ftp *.* LISTEN
142 tcp *.telnet *.* LISTEN
143 tcp *.smtp *.* LISTEN
144 ...
145 Active Internet (udp) Connections
147 Proto Local Address
148 udp *.echo
149 udp *.discard
150 udp *.daytime
151 udp *.chargen
152 udp *.time
153 ...
154 % snmpnetstat -v 2c -c public -Ci testhost
156 Name Mtu Network Address Ipkts Ierrs Opkts Oerrs Queue
158 eri0 1500 10.6.9/24 testhost 170548881 245601 687976 0 0
159 lo0 8232 127 localhost 7530982 0 7530982 0 0
160 Example of using snmpnetstat to show statistics about a specific proto‐
162 col:
163 % snmpnetstat -v 2c -c public -CP tcp testhost
165 Active Internet (tcp) Connections
167 Proto Local Address Foreign Address (state)
168 tcp *.echo *.* LISTEN
169 tcp *.discard *.* LISTEN
170 tcp *.daytime *.* LISTEN
171 tcp *.chargen *.* LISTEN
172 tcp *.ftp *.* LISTEN
173 tcp *.telnet *.* LISTEN
174 tcp *.smtp *.* LISTEN
175 ...
176
178 snmpcmd(1), iostat(1), vmstat(1), hosts(5), networks(5), protocols(5),
179 services(5).
180
182 The notion of errors is ill-defined.
1834.2 Berkeley Distribution 16 Nov 2006 SNMPNETSTAT(1)