2 # IP Virtual Server configuration
5 tristate "IP virtual server support"
6 depends on NET && INET && NETFILTER
7 depends on (NF_CONNTRACK || NF_CONNTRACK=n)
9 IP Virtual Server support will let you build a high-performance
10 virtual server based on cluster of two or more real servers. This
11 option must be enabled for at least one of the clustered computers
12 that will take care of intercepting incoming connections to a
13 single IP address and scheduling them to real servers.
15 Three request dispatching techniques are implemented, they are
16 virtual server via NAT, virtual server via tunneling and virtual
17 server via direct routing. The several scheduling algorithms can
18 be used to choose which server the connection is directed to,
19 thus load balancing can be achieved among the servers. For more
20 information and its administration program, please visit the
21 following URL: <http://www.linuxvirtualserver.org/>.
23 If you want to compile it in kernel, say Y. To compile it as a
24 module, choose M here. If unsure, say N.
29 bool "IPv6 support for IPVS"
30 depends on IPV6 = y || IP_VS = IPV6
31 select IP6_NF_IPTABLES
34 Add IPv6 support to IPVS.
39 bool "IP virtual server debugging"
41 Say Y here if you want to get additional messages useful in
42 debugging the IP virtual server code. You can change the debug
43 level in /proc/sys/net/ipv4/vs/debug_level
46 int "IPVS connection table size (the Nth power of 2)"
50 The IPVS connection hash table uses the chaining scheme to handle
51 hash collisions. Using a big IPVS connection hash table will greatly
52 reduce conflicts when there are hundreds of thousands of connections
55 Note the table size must be power of 2. The table size will be the
56 value of 2 to the your input number power. The number to choose is
57 from 8 to 20, the default number is 12, which means the table size
58 is 4096. Don't input the number too small, otherwise you will lose
59 performance on it. You can adapt the table size yourself, according
60 to your virtual server application. It is good to set the table size
61 not far less than the number of connections per second multiplying
62 average lasting time of connection in the table. For example, your
63 virtual server gets 200 connections per second, the connection lasts
64 for 200 seconds in average in the connection table, the table size
65 should be not far less than 200x200, it is good to set the table
68 Another note that each connection occupies 128 bytes effectively and
69 each hash entry uses 8 bytes, so you can estimate how much memory is
72 You can overwrite this number setting conn_tab_bits module parameter
73 or by appending ip_vs.conn_tab_bits=? to the kernel command line
74 if IP VS was compiled built-in.
76 comment "IPVS transport protocol load balancing support"
78 config IP_VS_PROTO_TCP
79 bool "TCP load balancing support"
81 This option enables support for load balancing TCP transport
82 protocol. Say Y if unsure.
84 config IP_VS_PROTO_UDP
85 bool "UDP load balancing support"
87 This option enables support for load balancing UDP transport
88 protocol. Say Y if unsure.
90 config IP_VS_PROTO_AH_ESP
91 def_bool IP_VS_PROTO_ESP || IP_VS_PROTO_AH
93 config IP_VS_PROTO_ESP
94 bool "ESP load balancing support"
96 This option enables support for load balancing ESP (Encapsulation
97 Security Payload) transport protocol. Say Y if unsure.
100 bool "AH load balancing support"
102 This option enables support for load balancing AH (Authentication
103 Header) transport protocol. Say Y if unsure.
105 config IP_VS_PROTO_SCTP
106 bool "SCTP load balancing support"
109 This option enables support for load balancing SCTP transport
110 protocol. Say Y if unsure.
112 comment "IPVS scheduler"
115 tristate "round-robin scheduling"
117 The robin-robin scheduling algorithm simply directs network
118 connections to different real servers in a round-robin manner.
120 If you want to compile it in kernel, say Y. To compile it as a
121 module, choose M here. If unsure, say N.
124 tristate "weighted round-robin scheduling"
126 The weighted robin-robin scheduling algorithm directs network
127 connections to different real servers based on server weights
128 in a round-robin manner. Servers with higher weights receive
129 new connections first than those with less weights, and servers
130 with higher weights get more connections than those with less
131 weights and servers with equal weights get equal connections.
133 If you want to compile it in kernel, say Y. To compile it as a
134 module, choose M here. If unsure, say N.
137 tristate "least-connection scheduling"
139 The least-connection scheduling algorithm directs network
140 connections to the server with the least number of active
143 If you want to compile it in kernel, say Y. To compile it as a
144 module, choose M here. If unsure, say N.
147 tristate "weighted least-connection scheduling"
149 The weighted least-connection scheduling algorithm directs network
150 connections to the server with the least active connections
151 normalized by the server weight.
153 If you want to compile it in kernel, say Y. To compile it as a
154 module, choose M here. If unsure, say N.
157 tristate "weighted failover scheduling"
159 The weighted failover scheduling algorithm directs network
160 connections to the server with the highest weight that is
163 If you want to compile it in kernel, say Y. To compile it as a
164 module, choose M here. If unsure, say N.
167 tristate "weighted overflow scheduling"
169 The weighted overflow scheduling algorithm directs network
170 connections to the server with the highest weight that is
171 currently available and overflows to the next when active
172 connections exceed the node's weight.
174 If you want to compile it in kernel, say Y. To compile it as a
175 module, choose M here. If unsure, say N.
178 tristate "locality-based least-connection scheduling"
180 The locality-based least-connection scheduling algorithm is for
181 destination IP load balancing. It is usually used in cache cluster.
182 This algorithm usually directs packet destined for an IP address to
183 its server if the server is alive and under load. If the server is
184 overloaded (its active connection numbers is larger than its weight)
185 and there is a server in its half load, then allocate the weighted
186 least-connection server to this IP address.
188 If you want to compile it in kernel, say Y. To compile it as a
189 module, choose M here. If unsure, say N.
192 tristate "locality-based least-connection with replication scheduling"
194 The locality-based least-connection with replication scheduling
195 algorithm is also for destination IP load balancing. It is
196 usually used in cache cluster. It differs from the LBLC scheduling
197 as follows: the load balancer maintains mappings from a target
198 to a set of server nodes that can serve the target. Requests for
199 a target are assigned to the least-connection node in the target's
200 server set. If all the node in the server set are over loaded,
201 it picks up a least-connection node in the cluster and adds it
202 in the sever set for the target. If the server set has not been
203 modified for the specified time, the most loaded node is removed
204 from the server set, in order to avoid high degree of replication.
206 If you want to compile it in kernel, say Y. To compile it as a
207 module, choose M here. If unsure, say N.
210 tristate "destination hashing scheduling"
212 The destination hashing scheduling algorithm assigns network
213 connections to the servers through looking up a statically assigned
214 hash table by their destination IP addresses.
216 If you want to compile it in kernel, say Y. To compile it as a
217 module, choose M here. If unsure, say N.
220 tristate "source hashing scheduling"
222 The source hashing scheduling algorithm assigns network
223 connections to the servers through looking up a statically assigned
224 hash table by their source IP addresses.
226 If you want to compile it in kernel, say Y. To compile it as a
227 module, choose M here. If unsure, say N.
230 tristate "shortest expected delay scheduling"
232 The shortest expected delay scheduling algorithm assigns network
233 connections to the server with the shortest expected delay. The
234 expected delay that the job will experience is (Ci + 1) / Ui if
235 sent to the ith server, in which Ci is the number of connections
236 on the ith server and Ui is the fixed service rate (weight)
239 If you want to compile it in kernel, say Y. To compile it as a
240 module, choose M here. If unsure, say N.
243 tristate "never queue scheduling"
245 The never queue scheduling algorithm adopts a two-speed model.
246 When there is an idle server available, the job will be sent to
247 the idle server, instead of waiting for a fast one. When there
248 is no idle server available, the job will be sent to the server
249 that minimize its expected delay (The Shortest Expected Delay
250 scheduling algorithm).
252 If you want to compile it in kernel, say Y. To compile it as a
253 module, choose M here. If unsure, say N.
255 comment 'IPVS SH scheduler'
257 config IP_VS_SH_TAB_BITS
258 int "IPVS source hashing table size (the Nth power of 2)"
262 The source hashing scheduler maps source IPs to destinations
263 stored in a hash table. This table is tiled by each destination
264 until all slots in the table are filled. When using weights to
265 allow destinations to receive more connections, the table is
266 tiled an amount proportional to the weights specified. The table
267 needs to be large enough to effectively fit all the destinations
268 multiplied by their respective weights.
270 comment 'IPVS application helper'
273 tristate "FTP protocol helper"
274 depends on IP_VS_PROTO_TCP && NF_CONNTRACK && NF_NAT && \
278 FTP is a protocol that transfers IP address and/or port number in
279 the payload. In the virtual server via Network Address Translation,
280 the IP address and port number of real servers cannot be sent to
281 clients in ftp connections directly, so FTP protocol helper is
282 required for tracking the connection and mangling it back to that of
285 If you want to compile it in kernel, say Y. To compile it as a
286 module, choose M here. If unsure, say N.
289 bool "Netfilter connection tracking"
290 depends on NF_CONNTRACK
292 The Netfilter connection tracking support allows the IPVS
293 connection state to be exported to the Netfilter framework
294 for filtering purposes.
297 tristate "SIP persistence engine"
298 depends on IP_VS_PROTO_UDP
299 depends on NF_CONNTRACK_SIP
301 Allow persistence based on the SIP Call-ID