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
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
|
<html>
<head>
<title>svlogd(8) manual page</title>
</head>
<body bgcolor='white'>
<a href='http://smarden.org/pape/'>G. Pape</a><br><a href='index.html'>runit</A><hr><p>
<h2><a name='sect0'>Name</a></h2>
svlogd - runit’s service logging daemon
<h2><a name='sect1'>Synopsis</a></h2>
<b>svlogd</b> [-ttv] [-r <i>c]</i> [-R
<i>xyz]</i> [-l <i>len]</i> [-b <i>buflen]</i> <i>logs</i>
<h2><a name='sect2'>Description</a></h2>
<i>logs</i> consists of one or more arguments,
each specifying a directory. <p>
<b>svlogd</b> continuously reads log data from its
standard input, optionally filters log messages, and writes the data to
one or more automatically rotated <i>logs</i>. <p>
Recent log files can automatically
be processed by an arbitrary processor program when they are rotated, and
<b>svlogd</b> can be told to alert selected log messages to standard error, and
through udp. <p>
<b>svlogd</b> runs until it sees end-of-file on standard input or is
sent a TERM signal, see below.
<h3><a name='sect3'>Log Directory</a></h3>
A log directory <i>log</i> contains
some number of old log files, and the current log file <i>current</i>. Old log
files have a file name starting with <i>@</i> followed by a precise timestamp
(see the daemontools’ <b>tai64n</b> program), indicating when <i>current</i> was rotated
and renamed to this file. <p>
A log directory additionally contains the lock
file <i>lock</i>, maybe <i>state</i> and <i>newstate</i>, and optionally the file <i>config</i>. <b>svlogd</b>
creates necessary files if they don’t exist. <p>
If <b>svlogd</b> has trouble opening
a log directory, it prints a warning, and ignores this log directory. If
<b>svlogd</b> is unable to open all log directories given at the command line,
it exits with an error. This can happen on start-up or after receiving a
HUP signal.
<h3><a name='sect4'>Log File Rotation</a></h3>
<b>svlogd</b> appends selected log messages to the
<i>current</i> log file. If <i>current</i> has <i>size</i> bytes or more (or there is a new-line
within the last <i>len</i> of <i>size</i> bytes), or is older than a specified amount
of <i>time</i>, <i>current</i> is rotated: <p>
<b>svlogd</b> closes <i>current</i>, changes permission
of <i>current</i> to 0755, renames <i>current</i> to @<i>timestamp.s,</i> and starts with a new
empty <i>current</i>. If <b>svlogd</b> sees <i>num</i> or more old log files in the log directory,
it removes the oldest one. Note that this doesn’t decrease the number of
log files if there are already more than <i>num</i> log files.
<h3><a name='sect5'>Processor</a></h3>
If <b>svlogd</b>
is told to process recent log files, it saves <i>current</i> to @<i>timestamp.u,</i> feeds
@<i>timestamp.u</i> through ‘‘sh -c "<i>processor</i>"’’ and writes the output to @<i>timestamp.t.</i>
If the <i>processor</i> finishes successfully, @<i>timestamp.t</i> is renamed to @<i>timestamp.s,</i>
and @<i>timestamp.u</i> is deleted; otherwise @<i>timestamp.t</i> is deleted and the <i>processor</i>
is started again. <b>svlogd</b> also saves any output that the <i>processor</i> writes
to file descriptor 5, and makes that output available on file descriptor
4 when running <i>processor</i> on the next log file rotation. <p>
A <i>processor</i> is run
in the background. If <b>svlogd</b> sees a previously started <i>processor</i> still running
when trying to start a new one for the same <i>log</i>, it blocks until the currently
running <i>processor</i> has finished successfully. Only the HUP signal works in
that situation. Note that this may block any program feeding its log data
to <b>svlogd.</b>
<p>
<h3><a name='sect6'>Config</a></h3>
On startup, and after receiving a HUP signal, <b>svlogd</b> checks
for each log directory <i>log</i> if the configuration file <i>log/config</i> exists,
and if so, reads the file line by line and adjusts configuration for <i>log</i>
as follows: <p>
If the line is empty, or starts with a ‘‘#’’, it is ignored. A line
of the form
<dl>
<dt>s<i>size</i> </dt>
<dd>sets the maximum file size of <i>current</i> when <b>svlogd</b> should
rotate the current log file to <i>size</i> bytes. Default is 1000000. If <i>size</i> is
zero, <b>svlogd</b> doesn’t rotate log files. You should set <i>size</i> to at least (2
* <i>len</i>). </dd>
<dt>n<i>num</i> </dt>
<dd>sets the number of old log files <b>svlogd</b> should maintain to
<i>num</i>. If <b>svlogd</b> sees more that <i>num</i> old log files in <i>log</i> after log file rotation,
it deletes the oldest one. Default is 10. If <i>num</i> is zero, <b>svlogd</b> doesn’t remove
old log files. </dd>
<dt>N<i>min</i> </dt>
<dd>sets the minimum number of old log files <b>svlogd</b> should
maintain to <i>min</i>. <i>min</i> must be less than <i>num</i>. If <i>min</i> is set, and <b>svlogd</b> cannot
write to <i>current</i> because the filesystem is full, and it sees more than
<i>min</i> old log files, it deletes the oldest one. </dd>
<dt>t<i>timeout</i> </dt>
<dd>sets the maximum
age of the <i>current</i> log file when <b>svlogd</b> should rotate the current log file
to <i>timeout</i> seconds. If <i>current</i> is <i>timeout</i> seconds old, and is not empty,
<b>svlogd</b> forces log file rotation. </dd>
<dt>!<i>processor</i> </dt>
<dd>tells <b>svlogd</b> to feed each recent
log file through <i>processor</i> (see above) on log file rotation. By default
log files are not processed. </dd>
<dt>u<i>a.b.c.d[:port]</i> </dt>
<dd>tells <b>svlogd</b> to transmit the first
<i>len</i> characters of selected log messages to the IP address <i>a.b.c.d</i>, port number
<i>port</i>. If <i>port</i> isn’t set, the default port for syslog is used (514). <i>len</i> can
be set through the -l option, see below. If <b>svlogd</b> has trouble sending udp
packets, it writes error messages to the log directory. Attention: logging
through udp is unreliable, and should be used in private networks only.
</dd>
<dt>U<i>a.b.c.d[:port]</i> </dt>
<dd>is the same as the <i>u</i> line above, but the log messages are
no longer written to the log directory, but transmitted through udp only.
Error messages from <b>svlogd</b> concerning sending udp packages still go to
the log directory. </dd>
<dt>p<i>prefix</i> </dt>
<dd>tells <b>svlogd</b> to prefix each line to be written
to the log directory, to standard error, or through UDP, with <i>prefix</i>. </dd>
</dl>
<p>
If
a line starts with a <i>-</i>, <i>+</i>, <i>e</i>, or <i>E</i>, <b>svlogd</b> matches the first <i>len</i> characters
of each log message against <i>pattern</i> and acts accordingly:
<dl>
<dt>-<i>pattern</i> </dt>
<dd>the log
message is deselected. </dd>
<dt>+<i>pattern</i> </dt>
<dd>the log message is selected. </dd>
<dt>e<i>pattern</i> </dt>
<dd>the
log message is selected to be printed to standard error. </dd>
<dt>E<i>pattern</i> </dt>
<dd>the log
message is deselected to be printed to standard error. </dd>
</dl>
<p>
Initially each line
is selected to be written to <i>log/current</i>. Deselected log messages are discarded
from <i>log</i>. Initially each line is deselected to be written to standard err.
Log messages selected for standard error are written to standard error.
<h2><a name='sect7'>Pattern Matching</a></h2>
<b>svlogd</b> matches a log message against the string <i>pattern</i>
as follows: <p>
<i>pattern</i> is applied to the log message one character by one,
starting with the first. A character not a star (‘‘*’’) and not a plus (‘‘+’’) matches
itself. A plus matches the next character in <i>pattern</i> in the log message
one or more times. A star before the end of <i>pattern</i> matches any string in
the log message that does not include the next character in <i>pattern</i>. A star
at the end of <i>pattern</i> matches any string. <p>
Timestamps optionally added by
<b>svlogd</b> are not considered part of the log message. <p>
An <b>svlogd</b> pattern is
not a regular expression. For example consider a log message like this <p>
2005-12-18_09:13:50.97618 tcpsvd: info: pid 1977 from 10.4.1.14<br>
<p>
The following pattern doesn’t match <p>
-*pid*<br>
<p>
because the first star matches up to the first p in tcpsvd, and then the
match fails because i is not s. To match this log message, you can use a
pattern like this instead <p>
-*: *: pid *<br>
<h2><a name='sect8'>Options</a></h2>
<dl>
<dt><b>-t</b> </dt>
<dd>timestamp. Prefix each selected line with a precise timestamp
(see the daemontools’ <b>tai64n</b> program) when writing to <i>log</i> or to standard
error. </dd>
<dt><b>-tt</b> </dt>
<dd>timestamp. Prefix each selected line with a human readable, sortable
UTC timestamp of the form YYYY-MM-DD_HH:MM:SS.xxxxx when writing to <i>log</i> or
to standard error. </dd>
<dt><b>-r <i>c</b> </i></dt>
<dd>replace. <i>c</i> must be a single character. Replace non-printable
characters in log messages with <i>c</i>. Characters are replaced before pattern
matching is applied. </dd>
<dt><b>-R <i>xyz</b> </i></dt>
<dd>replace charset. Additionally to non-printable
characters, replace all characters found in <i>xyz</i> with <i>c</i> (default ‘‘_’’). </dd>
<dt><b>-l <i>len</b>
</i></dt>
<dd>line length. Pattern matching applies to the first <i>len</i> characters of a log
message only. Default is 1000. </dd>
<dt><b>-b <i>buflen</b> </i></dt>
<dd>buffer size. Set the size of the buffer
<b>svlogd</b> uses when reading from standard input and writing to <i>logs</i> to <i>buflen</i>.
Default is 1024. <i>buflen</i> must be greater than <i>len</i>. </dd>
<dt><b>-v</b> </dt>
<dd>verbose. Print verbose
messages to standard error. </dd>
</dl>
<h2><a name='sect9'>Signals</a></h2>
If <b>svlogd</b> is sent a HUP signal, it closes
and reopens all <i>logs</i>, and updates their configuration according to <i>log/config</i>.
If <b>svlogd</b> has trouble opening a log directory, it prints a warning, and
discards this log directory. If <b>svlogd</b> is unable to open all log directories
given at the command line, it exits with an error. <p>
If <b>svlogd</b> is sent a TERM
signal, or if it sees end-of-file on standard input, it stops reading standard
input, processes the data in the buffer, waits for all <i>processor</i> subprocesses
to finish if any, and exits 0 as soon as possible. <p>
If <b>svlogd</b> is sent an
ALRM signal, it forces log file rotation for all <i>logs</i> with a non empty
<i>current</i> log file.
<h2><a name='sect10'>See Also</a></h2>
<i>sv(8)</i>, <i>runsv(8)</i>, <i>chpst(8)</i>, <i>runit(8)</i>, <i>runit-init(8)</i>,
<i>runsvdir(8)</i>, <i>runsvchdir(8)</i> <p>
<i>http://smarden.org/runit/</i>
<h2><a name='sect11'>Author</a></h2>
Gerrit Pape <pape@smarden.org>
<p>
<hr><p>
<a name='toc'><b>Table of Contents</b></a><p>
<ul>
<li><a name='toc0' href='#sect0'>Name</a></li>
<li><a name='toc1' href='#sect1'>Synopsis</a></li>
<li><a name='toc2' href='#sect2'>Description</a></li>
<ul>
<li><a name='toc3' href='#sect3'>Log Directory</a></li>
<li><a name='toc4' href='#sect4'>Log File Rotation</a></li>
<li><a name='toc5' href='#sect5'>Processor</a></li>
<li><a name='toc6' href='#sect6'>Config</a></li>
</ul>
<li><a name='toc7' href='#sect7'>Pattern Matching</a></li>
<li><a name='toc8' href='#sect8'>Options</a></li>
<li><a name='toc9' href='#sect9'>Signals</a></li>
<li><a name='toc10' href='#sect10'>See Also</a></li>
<li><a name='toc11' href='#sect11'>Author</a></li>
</ul>
</body>
</html>
|