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Fix bug #400721 - Fix bonding instructions

1 <?xml version="1.0" encoding="UTF-8"?>
2 <!DOCTYPE sections SYSTEM "/dtd/book.dtd">
3
4 <!-- The content of this document is licensed under the CC-BY-SA license -->
5 <!-- See http://creativecommons.org/licenses/by-sa/2.5 -->
6
7 <!-- $Header: /var/cvsroot/gentoo/xml/htdocs/doc/en/handbook/hb-net-modules.xml,v 1.27 2011/10/23 09:46:14 swift Exp $ -->
8
9 <sections>
10
11 <abstract>
12 Gentoo provides you flexible networking - here you are told about choosing
13 different DHCP clients, setting up bonding, bridging, VLANs and more.
14 </abstract>
15
16 <version>11</version>
17 <date>2013-08-15</date>
18
19 <section>
20 <title>Network Modules</title>
21 <body>
22
23 <p>
24 We now support modular networking scripts, which means we can easily add support
25 for new interface types and configuration modules while keeping compatibility
26 with existing ones.
27 </p>
28
29 <p>
30 Modules load by default if the package they need is installed. If you specify a
31 module here that doesn't have its package installed then you get an error
32 stating which package you need to install. Ideally, you only use the modules
33 setting when you have two or more packages installed that supply the same
34 service and you need to prefer one over the other.
35 </p>
36
37 <note>
38 All settings discussed here are stored in <path>/etc/conf.d/net</path> unless
39 otherwise specified.
40 </note>
41
42 <pre caption="Module preference">
43 <comment># Prefer ifconfig over iproute2</comment>
44 modules="ifconfig"
45
46 <comment># You can also specify other modules for an interface
47 # In this case we prefer pump over dhcpcd</comment>
48 modules_eth0="pump"
49
50 <comment># You can also specify which modules not to use - for example you may be
51 # using a supplicant or linux-wlan-ng to control wireless configuration but
52 # you still want to configure network settings per ESSID associated with.</comment>
53 modules="!iwconfig"
54 </pre>
55
56 </body>
57 </section>
58 <section>
59 <title>Interface Handlers</title>
60 <body>
61
62 <p>
63 We provide two interface handlers presently: <c>ifconfig</c> and
64 <c>iproute2</c>. You need one of these to do any kind of network configuration.
65 </p>
66
67 <p>
68 <c>ifconfig</c> is installed by default (the <c>net-tools</c> package is part of
69 the system profile). <c>iproute2</c> is a more powerful and flexible package,
70 but it's not included by default.
71 </p>
72
73 <pre caption="To install iproute2">
74 # <i>emerge sys-apps/iproute2</i>
75
76 <comment># To prefer ifconfig over iproute2 if both are installed as openrc prefers
77 # to use iproute2 then</comment>
78 modules="ifconfig"
79 </pre>
80
81 <p>
82 As both <c>ifconfig</c> and <c>iproute2</c> do very similar things we allow
83 their basic configuration to work with each other. For example both the below
84 code snippet work regardless of which module you are using.
85 </p>
86
87 <pre caption="ifconfig and iproute2 examples">
88 config_eth0="192.168.0.2/24"
89 config_eth0="192.168.0.2 netmask 255.255.255.0"
90
91 <comment># We can also specify broadcast</comment>
92 config_eth0="192.168.0.2/24 brd 192.168.0.255"
93 config_eth0="192.168.0.2 netmask 255.255.255.0 broadcast 192.168.0.255"
94 </pre>
95
96 </body>
97 </section>
98 <section id="dhcp">
99 <title>DHCP</title>
100 <body>
101
102 <p>
103 DHCP is a means of obtaining network information (IP address, DNS servers,
104 Gateway, etc) from a DHCP server. This means that if there is a DHCP server
105 running on the network, you just have to tell each client to use DHCP and it
106 sets up the network all by itself. Of course, you will have to configure for
107 other things like wireless, PPP or other things if required before you can use
108 DHCP.
109 </p>
110
111 <p>
112 DHCP can be provided by <c>dhclient</c>, <c>dhcpcd</c>, or <c>pump</c>. Each
113 DHCP module has its pros and cons - here's a quick run down.
114 </p>
115
116 <table>
117 <tr>
118 <th>DHCP Module</th>
119 <th>Package</th>
120 <th>Pros</th>
121 <th>Cons</th>
122 </tr>
123 <tr>
124 <ti><c>dhclient</c></ti>
125 <ti><c>net-misc/dhcp</c></ti>
126 <ti>
127 Made by ISC, the same people who make the BIND DNS software. Very
128 configurable
129 </ti>
130 <ti>
131 Configuration is overly complex, software is quite bloated, cannot get
132 NTP servers from DHCP, does not send hostname by default
133 </ti>
134 </tr>
135 <tr>
136 <ti><c>dhcpcd</c></ti>
137 <ti><c>net-misc/dhcpcd</c></ti>
138 <ti>
139 Long time Gentoo default, no reliance on outside tools, actively developed
140 by Gentoo
141 </ti>
142 <ti>Can be slow at times, does not yet daemonize when lease is infinite</ti>
143 </tr>
144 <tr>
145 <ti><c>pump</c></ti>
146 <ti><c>net-misc/pump</c></ti>
147 <ti>
148 Lightweight, no reliance on outside tools
149 </ti>
150 <ti>
151 No longer maintained upstream, unreliable, especially over modems, cannot
152 get NIS servers from DHCP
153 </ti>
154 </tr>
155 </table>
156
157 <p>
158 If you have more than one DHCP client installed, you need to specify which one
159 to use - otherwise we default to <c>dhcpcd</c> if available.
160 </p>
161
162 <p>
163 To send specific options to the DHCP module, use <c>module_eth0="..."</c>
164 <e>(change module to the DHCP module you're using - i.e. <c>dhcpcd_eth0</c>)</e>.
165 </p>
166
167 <p>
168 We try and make DHCP relatively agnostic - as such we support the following
169 commands using the <c>dhcp_eth0</c> variable. The default is not to set any of
170 them:
171 </p>
172
173 <ul>
174 <li><c>release</c> - releases the IP address for re-use</li>
175 <li><c>nodns</c> - don't overwrite <path>/etc/resolv.conf</path></li>
176 <li><c>nontp</c> - don't overwrite <path>/etc/ntp.conf</path></li>
177 <li><c>nonis</c> - don't overwrite <path>/etc/yp.conf</path></li>
178 </ul>
179
180 <pre caption="Sample DHCP configuration in /etc/conf.d/net">
181 <comment># Only needed if you have more than one DHCP module installed</comment>
182 modules="dhcpcd"
183
184 config_eth0="dhcp"
185 dhcpcd_eth0="-t 10" <comment># Timeout after 10 seconds</comment>
186 dhcp_eth0="release nodns nontp nonis" <comment># Only get an address</comment>
187 </pre>
188
189 <note>
190 <c>dhcpcd</c> and <c>pump</c> send the current hostname to the
191 DHCP server by default so you don't need to specify this anymore.
192 </note>
193
194 </body>
195 </section>
196 <section>
197 <title>ADSL with PPPoE/PPPoA</title>
198 <body>
199
200 <p>
201 First we need to install the ADSL software.
202 </p>
203
204 <pre caption="Install the ppp package">
205 # <i>emerge net-dialup/ppp</i>
206 </pre>
207
208 <p>
209 Second, create the PPP net script and the net script for the ethernet interface
210 to be used by PPP:
211 </p>
212
213 <pre caption="Creating the PPP and ethernet scripts">
214 # <i>ln -s /etc/init.d/net.lo /etc/init.d/net.ppp0</i>
215 # <i>ln -s /etc/init.d/net.lo /etc/init.d/net.eth0</i>
216 </pre>
217
218 <p>
219 Be sure to set <c>rc_depend_strict</c> to "YES" in <path>/etc/rc.conf</path>.
220 </p>
221
222 <p>
223 Now we need to configure <path>/etc/conf.d/net</path>.
224 </p>
225
226 <pre caption="A basic PPPoE setup">
227 config_eth0=null <comment>(Specify your ethernet interface)</comment>
228 config_ppp0="ppp"
229 link_ppp0="eth0" <comment>(Specify your ethernet interface)</comment>
230 plugins_ppp0="pppoe"
231 username_ppp0='user'
232 password_ppp0='password'
233 pppd_ppp0="
234 noauth
235 defaultroute
236 usepeerdns
237 holdoff 3
238 child-timeout 60
239 lcp-echo-interval 15
240 lcp-echo-failure 3
241 noaccomp noccp nobsdcomp nodeflate nopcomp novj novjccomp"
242
243 rc_need_ppp0="net.eth0"
244 </pre>
245
246 <p>
247 You can also set your password in <path>/etc/ppp/pap-secrets</path>.
248 </p>
249
250 <pre caption="Sample /etc/ppp/pap-secrets">
251 <comment># The * is important</comment>
252 "username" * "password"
253 </pre>
254
255 <p>
256 If you use PPPoE with a USB modem you'll need to emerge <c>br2684ctl</c>. Please
257 read <path>/usr/portage/net-dialup/speedtouch-usb/files/README</path> for
258 information on how to properly configure it.
259 </p>
260
261 <impo>
262 Please carefully read the section on ADSL and PPP in
263 <path>/usr/share/doc/openrc-0.8.3-r1/net.example.bz2</path>. It contains many
264 more detailed explanations of all the settings your particular PPP setup will
265 likely need. Of course, change <c>0.8.3-r1</c> with the version of OpenRC
266 installed on your system.
267 </impo>
268
269 </body>
270 </section>
271 <section id="apipa">
272 <title>APIPA (Automatic Private IP Addressing)</title>
273 <body>
274
275 <p>
276 APIPA tries to find a free address in the range 169.254.0.0-169.254.255.255 by
277 arping a random address in that range on the interface. If no reply is found
278 then we assign that address to the interface.
279 </p>
280
281 <p>
282 This is only useful for LANs where there is no DHCP server and you don't connect
283 directly to the internet and all other computers use APIPA.
284 </p>
285
286 <p>
287 For APIPA support, emerge <c>net-misc/iputils</c> or <c>net-analyzer/arping</c>.
288 </p>
289
290 <pre caption="APIPA configuration in /etc/conf.d/net">
291 <comment># Try DHCP first - if that fails then fallback to APIPA</comment>
292 config_eth0="dhcp"
293 fallback_eth0="apipa"
294
295 <comment># Just use APIPA</comment>
296 config_eth0="apipa"
297 </pre>
298
299 </body>
300 </section>
301 <section>
302 <title>Bonding</title>
303 <body>
304
305 <p>
306 For link bonding/trunking emerge <c>net-misc/ifenslave</c>.
307 </p>
308
309 <p>
310 Bonding is used to increase network bandwidth. If you have two network cards
311 going to the same network, you can bond them together so your applications see
312 just one interface but they really use both network cards.
313 </p>
314
315 <p>
316 First, clear the configuration of the participating interfaces:
317 </p>
318
319 <pre caption="Clearing interface configuration in /etc/conf.d/net">
320 config_eth0="null"
321 config_eth1="null"
322 config_eth2="null"
323 </pre>
324
325 <p>
326 Next, define the bonding between the interfaces:
327 </p>
328
329 <pre caption="Define the bonding">
330 slaves_bond0="eth0 eth1 eth2"
331 config_bond0="192.168.100.4/24"
332 </pre>
333
334 <p>
335 Remove the <path>net.eth*</path> services from the runlevels, create a
336 <path>net.bond0</path> one and add that one to the correct runlevel.
337 </p>
338
339 </body>
340 </section>
341 <section>
342 <title>Bridging (802.1d support)</title>
343 <body>
344
345 <p>
346 For bridging support emerge <c>net-misc/bridge-utils</c>.
347 </p>
348
349 <p>
350 Bridging is used to join networks together. For example, you may have a server
351 that connects to the internet via an ADSL modem and a wireless access card to
352 enable other computers to connect to the internet via the ADSL modem. You could
353 create a bridge to join the two interfaces together.
354 </p>
355
356 <pre caption="Bridge configuration in /etc/conf.d/net">
357 <comment># Configure the bridge - "man brctl" for more details</comment>
358 brctl_br0="setfd 0" "sethello 0" "stp off"
359
360 <comment># To add ports to bridge br0</comment>
361 bridge_br0="eth0 eth1"
362
363 <comment># You need to configure the ports to null values so dhcp does not get started</comment>
364 config_eth0="null"
365 config_eth1="null"
366
367 <comment># Finally give the bridge an address - you could use DHCP as well</comment>
368 config_br0="192.168.0.1/24"
369
370 <comment># Depend on eth0 and eth1 as they may require extra configuration</comment>
371 rc_need_br0="net.eth0 net.eth1"
372 </pre>
373
374 <impo>
375 For using some bridge setups, you may need to consult the <uri
376 link="?part=4&amp;chap=2#variable_name">variable name</uri> documentation.
377 </impo>
378
379 </body>
380 </section>
381 <section>
382 <title>MAC Address</title>
383 <body>
384
385 <p>
386 If you need to, you can change the MAC address of your interfaces through
387 the network configuration file too.
388 </p>
389
390 <pre caption="MAC Address change example">
391 <comment># To set the MAC address of the interface</comment>
392 mac_eth0="00:11:22:33:44:55"
393
394 <comment># To randomize the last 3 bytes only</comment>
395 mac_eth0="random-ending"
396
397 <comment># To randomize between the same physical type of connection (e.g. fibre,
398 # copper, wireless) , all vendors</comment>
399 mac_eth0="random-samekind"
400
401 <comment># To randomize between any physical type of connection (e.g. fibre, copper,
402 # wireless) , all vendors</comment>
403 mac_eth0="random-anykind"
404
405 <comment># Full randomization - WARNING: some MAC addresses generated by this may
406 # NOT act as expected</comment>
407 mac_eth0="random-full"
408 </pre>
409
410 </body>
411 </section>
412 <section>
413 <title>Tunnelling</title>
414 <body>
415
416 <p>
417 You don't need to emerge anything for tunnelling as the interface handler can do
418 it for you.
419 </p>
420
421 <pre caption="Tunnelling configuration in /etc/conf.d/net">
422 <comment># For GRE tunnels</comment>
423 iptunnel_vpn0="mode gre remote 207.170.82.1 key 0xffffffff ttl 255"
424
425 <comment># For IPIP tunnels</comment>
426 iptunnel_vpn0="mode ipip remote 207.170.82.2 ttl 255"
427
428 <comment># To configure the interface</comment>
429 config_vpn0="192.168.0.2 peer 192.168.1.1"
430 </pre>
431
432 </body>
433 </section>
434 <section>
435 <title>VLAN (802.1q support)</title>
436 <body>
437
438 <p>
439 For VLAN support, emerge <c>net-misc/vconfig</c>. Also make sure that you use
440 iproute2 as configuration module rather than ifconfig.
441 </p>
442
443 <p>
444 Virtual LAN is a group of network devices that behave as if they were connected
445 to a single network segment - even though they may not be. VLAN members can only
446 see members of the same VLAN even though they may share the same physical
447 network.
448 </p>
449
450 <p>
451 To configure VLANs, first specify the VLAN numbers in
452 <path>/etc/conf.d/net</path> like so:
453 </p>
454
455 <pre caption="Specifying VLAN numbers">
456 vlans_eth0="1 2"
457 </pre>
458
459 <p>
460 Next, configure the interface for each VLAN:
461 </p>
462
463 <pre caption="Interface configuration for each VLAN">
464 config_eth0_1="172.16.3.1 netmask 255.255.254.0"
465 routes_eth0_1="default via 172.16.3.254"
466
467 config_eth0_2="172.16.2.1 netmask 255.255.254.0"
468 routes_eth0_2="default via 172.16.2.254"
469 </pre>
470
471 <p>
472 VLAN-specific configurations are handled by <c>vconfig</c> like so:
473 </p>
474
475 <pre caption="Configuring the VLANs">
476 vlan1_name="vlan1"
477 vlan1_ingress="2:6 3:5"
478 eth0_vlan1_egress="1:2"
479 </pre>
480
481 <impo>
482 For using some VLAN setups, you may need to consult the <uri
483 link="?part=4&amp;chap=2#variable_name">variable name</uri> documentation.
484 </impo>
485
486 </body>
487 </section>
488
489 </sections>

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