summaryrefslogtreecommitdiff
path: root/docs/ch15-troubleshooting.rst
blob: 47abab04e5822941d9311af27d4edf889082c839 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
Troubleshooting
===============

Sometimes things break or don't work as expected. This section describes
several troubleshooting tools provided by VyOS that can help when something
goes wrong.

Basic Connectivity Verification
-------------------------------

Verifying connectivity can be done with the familiar `ping` and `traceroute`
commands. The options for each are shown (the options for each command were
displayed using the built-in help as described in the `Command-Line Interface`_
section and are omitted from the output here):

.. code-block:: sh

  vyos@vyos:~$ ping
  Possible completions:
    <hostname>    Send Internet Control Message Protocol (ICMP) echo request
    <x.x.x.x>
    <h:h:h:h:h:h:h:h>

Several options are available when more extensive troubleshooting is needed:

.. code-block:: sh

  vyos@vyos:~$ ping 8.8.8.8
  Possible completions:
    <Enter>       Execute the current command
    adaptive      Ping options
    allow-broadcast
    audible
    bypass-route
    count
    deadline
    flood
    interface
    interval
    mark
    no-loopback
    numeric
    pattern
    quiet
    record-route
    size
    timestamp
    tos
    ttl
    verbose

.. code-block:: sh

  vyos@vyos:~$ traceroute
  Possible completions:
    <hostname>    Track network path to specified node
    <x.x.x.x>
    <h:h:h:h:h:h:h:h>
    ipv4          Track network path to <hostname|IPv4 address>
    ipv6          Track network path to <hostname|IPv6 address>

However, another tool, mtr_, is available which combines ping and traceroute
into a single tool. An example of its output is shown:

.. code-block:: sh

  vyos@vyos:~$ mtr 10.62.212.12

                             My traceroute  [v0.85]
  vyos (0.0.0.0)
  Keys:  Help   Display mode   Restart statistics   Order of fields   quit
                                    Packets               Pings
  Host                            Loss%   Snt   Last   Avg  Best  Wrst StDev
  1. 10.11.110.4                   0.0%    34    0.5   0.5   0.4   0.8   0.1
  2. 10.62.255.184                 0.0%    34    1.1   1.0   0.9   1.4   0.1
  3. 10.62.255.71                  0.0%    34    1.4   1.4   1.3   2.0   0.1
  4. 10.62.212.12                  0.0%    34    1.6   1.6   1.6   1.7   0.0

**NOTE:** The output of '''mtr''' consumes the screen and will replace your
command prompt.

Several options are available for changing the display output. Press `h` to
invoke the built in help system. To quit, just press `q` and you'll be returned
to the VyOS command prompt.

Monitoring Network Interfaces
-----------------------------

It's possible to monitor network traffic, either at the flow level or protocol
level. This can be useful when troubleshooting a variety of protocols and
configurations. The following interface types can be monitored:

.. code-block:: sh

  vyos@vyos:~$ monitor interfaces
  Possible completions:
    <Enter>       Execute the current command
    bonding       Monitor a bonding interface
    bridge        Monitor a bridge interface
    ethernet      Monitor a ethernet interface
    loopback      Monitor a loopback interface
    openvpn       Monitor an openvpn interface
    pppoe         Monitor pppoe interface
    pseudo-ethernet
                  Monitor a pseudo-ethernet interface
    tunnel        Monitor a tunnel interface
    vrrp          Monitor a vrrp interface
    vti           Monitor a vti interface
    wireless      Monitor wireless interface

To monitor traffic flows, issue the :code:`monitor interfaces <type> <name> flow`
command, replacing `<type>` and `<name>` with your desired interface type and
name, respectively. Output looks like the following:

.. code-block:: sh

                     12.5Kb              25.0Kb              37.5Kb              50.0Kb        62.5Kb
  ????????????????????????????????????????????????????????????????????????????????????????????????????
  10.11.111.255                        => 10.11.110.37                            0b      0b      0b
                                      <=                                       624b    749b    749b
  10.11.110.29                         => 10.62.200.11                            0b    198b    198b
                                      <=                                         0b    356b    356b
  255.255.255.255                      => 10.11.110.47                            0b      0b      0b
                                      <=                                       724b    145b    145b
  10.11.111.255                        => 10.11.110.47                            0b      0b      0b
                                      <=                                       724b    145b    145b
  10.11.111.255                        => 10.11.110.255                           0b      0b      0b
                                      <=                                       680b    136b    136b
  ????????????????????????????????????????????????????????????????????????????????????????????????????
  TX:             cumm:  26.7KB   peak:   40.6Kb                      rates:   23.2Kb  21.4Kb  21.4Kb
  RX:                    67.5KB           63.6Kb                               54.6Kb  54.0Kb  54.0Kb
  TOTAL:                 94.2KB            104Kb                               77.8Kb  75.4Kb  75.4Kb

Several options are available for changing the display output. Press `h` to
invoke the built in help system. To quit, just press `q` and you'll be returned
to the VyOS command prompt.

To monitor interface traffic, issue the :code:`monitor interfaces <type> <name>
traffic` command, replacing `<type>` and `<name>` with your desired interface
type and name, respectively. This command invokes the familiar tshark_ utility
and the following options are available:

.. code-block:: sh

  vyos@vyos:~$ monitor interfaces ethernet eth0 traffic
  Possible completions:
    <Enter>       Execute the current command
    detail        Monitor detailed traffic for the specified ethernet interface
    filter        Monitor filtered traffic for the specified ethernet interface
    save          Save monitored traffic to a file
    unlimited     Monitor traffic for the specified ethernet interface

To quit monitoring, press `Ctrl-c` and you'll be returned to the VyOS command
prompt. The `detail` keyword provides verbose output of the traffic seen on
the monitored interface. The `filter` keyword accepts valid `PCAP filter
expressions`_, enclosed in single or double quotes (e.g. "port 25" or "port 161
and udp"). The `save` keyword allows you to save the traffic dump to a file.
The `unlimited` keyword is used to specify that an unlimited number of packets
can be captured (by default, 1,000 packets are captured and you're returned to
the VyOS command prompt).

.. _mtr: http://www.bitwizard.nl/mtr/
.. _tshark: https://www.wireshark.org/docs/man-pages/tshark.html
.. _`PCAP filter expressions`: http://www.tcpdump.org/manpages/pcap-filter.7.html