1LVS.CF(5) File Formats Manual LVS.CF(5)
2
6 lvs.cf - configuration file for lvs
7
9 This file contains the configuration information for piranha and is
10 normally located in /etc/sysconfig/ha/lvs.cf. lvs.cf is read and
11 updated from the piranha web configuration tool, which uses lvs(8) to
12 actually work with the file.
13
15 Global settings affect all aspects of the cluster, including virtual
16 servers and real servers.
17 service = [lvs|fos]
19 Indicates which set of defined services are to be used. Virtual
20 Servers and Failover Services as mutually exclusive; although
21 they may both be defined in the same config file, thay cannot
22 both be running simultaneously. This option specifies which
23 section is to be used.
24 primary = a.b.c.d
26 This is the IP (or hostname) of the primary LVS machine.
27 primary_private = a.b.c.d
29 Indicates the IP address of an alternative network device for
30 private heartbeating. It is not necessary to fill out this
31 field for piranha to work as it simply provides an alternative
32 method of checking an IP service is running.
33 backup = a.b.c.d
35 This is the IP (or hostname) of the backup (or failover) LVS
36 machine.
37 backup_private = a.b.c.d
39 This is akin to primary_private but refers to the alternative IP
40 device on the backup
41 backup_active = [0|1]
43 This dictates if the backup server option is active or inactive.
44 This option must be set if the backup server is to function in a
45 failover manner.
46 syncdaemon = [0|1]
48 This option dictates if the connection synchronization daemon is
49 active or inactive. This option is only useful when a backup
50 server is defined. See ipvsadm(8) for more information.
51 syncd_iface = dev
53 This option dictates the network interface that the synchroniza‐
54 tion daemon should use for sending and receiving multicast mes‐
55 sages.
56 syncd_id = n
58 This option dictates the syncid to be used by the synchroniza‐
59 tion daemon. Valid values for syncd_id are 0 to 255. The default
60 is 0.
61 heartbeat = [0|1]
63 Use heartbeat between the two LVS nodes.
64 keepalive = n
66 Number of seconds between heartbeats.
67 deadtime = n
69 Length of time before a node is declared dead and IP takeover
70 occurs.
71 reservation_conflict_action = [nothing|preempt]
73 This option dictates what action should be taken when a scsi
74 reservation conflict occurs during failover and the disk is
75 found to be unexpectedly locked. You should think carefully
76 about this option as your setup may or may not have a scsi con‐
77 troller setup to reset the scsi bus on power on or warm reboot.
78 debug = NONE
80 Ignore this option. Eventually it will become a means to dictate
81 how much and what type of information about the state of the
82 cluster is written to file.
83 hard_shutdown = [0|1]
85 With this option (default 1) it is possible to have partially
86 running system. So problem with one nanny won't stop all others.
87 rsh_command =
89 The command family used to sync file systems and config files.
90 Allowable options are either rsh (default) or ssh. The appro‐
91 priate .rhosts (or .ssh/authorized_keys) entries must be on all
92 nodes so that connections can be made non-interactively.
93 Sync'ing of specified config files and directories will occur
95 when lvs receives a SIGUSR1. lvs.cf(5) is automatically synced
96 between the LVS nodes anytime it is written to.
97 network = [direct|nat|tunnel]
99 The lvs virtual server can reroute all of its incoming traffic
100 via one of three methods; NAT (Network Address Translation),
101 Direct Routing, or Tunneling (IP Encapsulation).
102 nat_router = a.b.c.d dev:n
104 If NAT routing is selected, this specifies the IP address and
105 device of the routing interface.
106 nat_nmask = a.b.c.d
108 Optional. The subnet mask to apply to nat_router.
109 tcp_timeout = n
111 This option specifies the timeout (in seconds) for TCP sessions.
112 A timeout value 0 means that the current timeout value is pre‐
113 served. Default timeout value is 0.
114 tcpfin_timeout = n
116 This option specifies the timeout (in seconds) for TCP sessions
117 after receiving a FIN packet. A timeout value 0 means that the
118 current timeout value is preserved. Default timeout value is 0.
119 udp_timeout = n
121 This option specifies the timeout (in seconds) for UDP packets.
122 A timeout value 0 means that the current timeout value is pre‐
123 served. Default timeout value is 0.
124
126 A per-virtual server section starts with
127 virtual server-name {
129 }
131 where the string is a unique server identifier. This doesn't have to
133 match up to a FQDN.
134 The following items are required for each virtual server entry in the
136 config file.
137 address = a.b.c.d
139 This is the address to be used for the virtual server.
140 sorry_server = a.b.c.d
142 This is the address to be used for the 'sorry' server. If spec‐
143 ified, requests for this virtual server will be redirected to
144 this IP address in the event that no real servers are available
145 to handle the request.
146 vip_nmask = a.b.c.d
148 Optional. This is the subnet mask to apply to the address of the
149 virtual server.
150 active = [0|1]
152 This flag is used to indicate whether or not this particular
153 virtual server is active. If it is marked inactive, then all
154 real servers being routed to by it will by default become inac‐
155 tive as well.
156 The following items are all optional entries (note the default
158 values for many).
159 load_monitor = [uptime|rup|ruptime|none]
161 This specifies the method that the LVS can acquire CPU load
162 information from the real servers. This load information is
163 used to adjust the weighting factor for each server entry in the
164 LVS routing table. Each method requires slightly different con‐
165 figurations to be present on the real servers and on the LVS
166 nodes. The default method is uptime. Specifying "none" causes
167 the service monitor to skip load tests (required for most non-
168 linux systems).
169 timeout =
171 This is the amount of time allowed before a presumed dead real
172 server is removed from the LVS routing table. Default is 10
173 seconds.
174 reentry =
176 This is the amount of time that a previously dead real server
177 must be alive before the LVS will re-enter it into the routing
178 table. The purpose of this delay is to prevent troubled
179 machines from causing a "ping-pong" effect. The default is 180
180 seconds.
181 port = xx
183 This is the port that the virtual server is instructed to listen
184 to and redirect network requests from. The default is port 80
185 (http).
186 send = xxx
188 If present, the specified text ("xxx") will be sent to the port
189 of the virtual server as part of the test for whether the ser‐
190 vice is operational. The text is limited to 255 characters maxi‐
191 mum. Characters must be printable/quotable, and may contain "\n,
192 \r, \\, or \'". Note that if both "send" and "expect" are spec‐
193 ified, the send will always execute before the read for the
194 expect is attempted.
195 send_program = path %h
197 For more advanced service verification, you can use this direc‐
198 tive to specify the path to a service-checking script. This
199 functionality is especially helpful for services that require
200 dynamically changing data, such as HTTPS or SSL. To use this
201 functionality, you must write a script that returns a textual
202 response (that will be matched against 'expect' directive), set
203 it to be executable, and specify the path to it. To ensure that
204 each server in the real server pool is checked, use the special
205 token %h after the path to the script. This token is replaced
206 with each real server's IP address as the script is called by
207 the nanny daemon. If 'send_program' is used, then the 'send' is
208 ignored.
209 expect = xxx
211 If present, the specified text ("xxx") will be expected as a
212 response from the port on the virtual server as part of the test
213 for whether the service is operational. The text is limited to
214 255 characters maximum. Characters must be printable/quotable,
215 and may contain "\n, \r, \\, or \'". Note that if both "send"
216 and "expect" are specified, the send will always execute before
217 the read for the expect is attempted. If you wrote your own
218 service-checking script, enter the response you told it to send
219 if it was successful.
220 use_regex = [0|1]
222 If enabled, the expect string will be interpreted as a regular
223 expression.
224 persistent =
226 The number of seconds that a connection between this virtual
227 server and a real server will persist. If a request is received
228 from a client within this number of seconds, it will be assigned
229 to the same real server that processed a prior request. If this
230 parameter is missing or set to zero, connections with this vir‐
231 tual server are not persistent.
232 pmask =
234 The network mask to apply to persistence if enabled. Default is
235 255.255.255.255.
236 scheduler = [rr|lc|wlc|wrr]
238 This is the key part of the LVS router. These methods of sched‐
239 uling how incoming requests are routed are built as loadable
240 kernel modules: Round Robin (rr), least-connections (lc),
241 Weighted Least Connections (wlc, the default) and Weighted Round
242 Robin (wrr).
243 REAL SERVER SECTIONS
245 A per-real server section starts with
246 server servername {
248 }
250 where the string is a unique server identifier. This doesn't have to
252 match up to any real FQDN.
253 The following items are required for each real server entry in the con‐
255 fig file.
256 address = a.b.c.d
258 This is the actual IP address being used by the real server. In
259 the cases of NAT type routing, it is generally one of the
260 reserved, private IPs.
261 active = [0|1]
263 This flag is used to indicate whether or not this particular
264 real server is active.
265 The following item is optional.
267 weight =
269 This option enforces a skew affect by enabling more loading on a
270 particular server. The weights of all real servers influence
271 the scheduling algorithm and a higher weight will load a partic‐
272 ular server down with more redirects. The default value is 1.
273 An example real server entry might look like:
275 server 1 {
277 address = 192.168.10.2
278 active = 1
279 weight = 1
280 }
281
284 A per-failover-service section starts with
285 failover service-name {
287 }
288 where the service-name is a unique identifier.
290 The following items are required for each failover service entry in the
292 config file.
293 address = a.b.c.d dev:x
295 This is the address and device interface to be used for the vir‐
296 tual service.
297 vip_nmask = a.b.c.d
299 Optional. The netmask to apply to the service address.
300 active = [0|1]
302 This flag is used to indicate whether or not this particular
303 virtual server is active. If it is marked inactive, then all
304 real servers being routed to by it will by default become inac‐
305 tive as well.
306 The following items are all optional entries (note the default
308 values for many).
309 timeout =
311 This is the amount of time allowed before a service is presumed
312 dead and will cause a failover.
313 reentry =
315 This is the amount of time that a previously dead partner system
316 must be alive before it will be a candidate for possible
317 failover. The purpose of this delay is to prevent troubled
318 machines from causing a "ping-pong" effect. The default is 180
319 seconds.
320 port = xx
322 This is the port that the failover service is instructed to
323 test. The default is port 80 (http).
324 send = xxx
326 If present, the specified text ("xxx") will be sent to the port
327 of the virtual server as part of the test for whether the ser‐
328 vice is operational. The text is limited to 255 characters maxi‐
329 mum. Characters must be printable/quotable, and may contain "\n,
330 \r, \\, or \'". Note that if both "send" and "expect" are spec‐
331 ified, the send will always execute before the read for the
332 expect is attempted.
333 expect = xxx
335 If present, the specified text ("xxx") will be expected as a
336 response from the port on the virtual server as part of the test
337 for whether the service is operational. The text is limited to
338 255 characters maximum. Characters must be printable/quotable,
339 and may contain "\n, \r, \\, or \'". Expect can also be a sin‐
340 gle '*' character to indicate any response characters are
341 allowed. Note that if both "send" and "expect" are specified,
342 the send will always execute before the read for the expect is
343 attempted.
344 start_cmd = xxx
346 Mandatory; specifies the startup command/script to execute to
347 start the failover service. Options can be specified, but must
348 be separated by a single space.
349 stop_cmd = xxx
351 Mandatory; specifies the shutdown command/script to execute to
352 stop the failover service. Options can be specified, but must be
353 separated by a single space.
354
357 ipvsadm(8), lvs(8), fos(8), pulse(8). sample.cf file
358 http://www.linuxvirtualserver.org
359 4 July 2001 LVS.CF(5)