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should be man brctl now, bug 197893

1 swift 1.1 <?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 swift 1.2 <!-- See http://creativecommons.org/licenses/by-sa/2.5 -->
6 swift 1.1
7 nightmorph 1.24 <!-- $Header: /var/cvsroot/gentoo/xml/htdocs/doc/en/handbook/hb-net-modules.xml,v 1.23 2007/04/14 02:39:25 nightmorph Exp $ -->
8 neysx 1.5
9 swift 1.1 <sections>
10    
11 neysx 1.19 <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 nightmorph 1.24 <version>8.3</version>
17     <date>2007-11-02</date>
18 swift 1.1
19     <section>
20     <title>Network Modules</title>
21     <body>
22    
23     <p>
24 jkt 1.9 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 swift 1.1 </p>
28    
29     <p>
30 jkt 1.9 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 swift 1.1 </p>
36    
37 vapier 1.15 <note>
38     All settings discussed here are stored in <path>/etc/conf.d/net</path> unless
39     otherwise specified.
40     </note>
41    
42 swift 1.1 <pre caption="Module preference">
43     <comment># Prefer iproute2 over ifconfig</comment>
44     modules=( "iproute2" )
45    
46     <comment># You can also specify other modules for an interface
47     # In this case we prefer udhcpc over dhcpcd</comment>
48     modules_eth0=( "udhcpc" )
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 jkt 1.10 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 swift 1.1 </p>
66    
67     <p>
68 jkt 1.10 <c>ifconfig</c> is the current Gentoo default and it's included in the system
69     profile. <c>iproute2</c> is a more powerful and flexible package, but it's not
70     included by default.
71 swift 1.1 </p>
72    
73     <pre caption="To install iproute2">
74     # <i>emerge sys-apps/iproute2</i>
75    
76     <comment># To prefer iproute2 over ifconfig if both are installed</comment>
77     modules=( "iproute2" )
78     </pre>
79    
80     <p>
81 jkt 1.10 As both <c>ifconfig</c> and <c>iproute2</c> do very similar things we allow
82     their basic configuration to work with each other. For example both the below
83     code snippet work regardless of which module you are using.
84 swift 1.1 </p>
85    
86     <pre caption="ifconfig and iproute2 examples">
87     config_eth0=( "192.168.0.2/24" )
88     config_eth0=( "192.168.0.2 netmask 255.255.255.0" )
89    
90     <comment># We can also specify broadcast</comment>
91     config_eth0=( "192.168.0.2/24 brd 192.168.0.255" )
92     config_eth0=( "192.168.0.2 netmask 255.255.255.0 broadcast 192.168.0.255" )
93     </pre>
94    
95     </body>
96     </section>
97     <section id="dhcp">
98     <title>DHCP</title>
99     <body>
100    
101     <p>
102     DHCP is a means of obtaining network information (IP address, DNS servers,
103     Gateway, etc) from a DHCP server. This means that if there is a DHCP server
104     running on the network, you just have to tell each client to use DHCP and it
105     sets up the network all by itself. Of course, you will have to configure for
106 jkt 1.10 other things like wireless, PPP or other things if required before you can use
107 swift 1.1 DHCP.
108     </p>
109    
110     <p>
111 jkt 1.10 DHCP can be provided by <c>dhclient</c>, <c>dhcpcd</c>, <c>pump</c> or
112     <c>udhcpc</c>. Each DHCP module has its pros and cons - here's a quick run down.
113 swift 1.1 </p>
114    
115     <table>
116 swift 1.2 <tr>
117     <th>DHCP Module</th>
118     <th>Package</th>
119     <th>Pros</th>
120     <th>Cons</th>
121     </tr>
122     <tr>
123 jkt 1.10 <ti><c>dhclient</c></ti>
124     <ti><c>net-misc/dhcp</c></ti>
125 swift 1.2 <ti>
126 swift 1.3 Made by ISC, the same people who make the BIND DNS software. Very
127     configurable
128 swift 1.2 </ti>
129     <ti>
130 swift 1.3 Configuration is overly complex, software is quite bloated, cannot get
131     NTP servers from DHCP, does not send hostname by default
132 swift 1.2 </ti>
133     </tr>
134     <tr>
135 jkt 1.10 <ti><c>dhcpcd</c></ti>
136     <ti><c>net-misc/dhcpcd</c></ti>
137 swift 1.2 <ti>
138 nightmorph 1.20 Long time Gentoo default, no reliance on outside tools, actively developed
139     by Gentoo
140 swift 1.2 </ti>
141 nightmorph 1.20 <ti>Can be slow at times, does not yet daemonize when lease is infinite</ti>
142 swift 1.2 </tr>
143     <tr>
144 jkt 1.10 <ti><c>pump</c></ti>
145     <ti><c>net-misc/pump</c></ti>
146 swift 1.2 <ti>
147 swift 1.3 Lightweight, no reliance on outside tools
148 swift 1.2 </ti>
149     <ti>
150 swift 1.3 No longer maintained upstream, unreliable, especially over modems, cannot
151     get NIS servers from DHCP
152 swift 1.2 </ti>
153     </tr>
154     <tr>
155 jkt 1.10 <ti><c>udhcpc</c></ti>
156     <ti><c>net-misc/udhcp</c></ti>
157 swift 1.2 <ti>
158 jkt 1.10 Lightweight - smallest DHCP client around, made for embedded systems
159 swift 1.2 </ti>
160     <ti>
161 swift 1.3 Unproven - no distro uses it by default, cannot define a timeout beyond 3
162     seconds
163 swift 1.2 </ti>
164     </tr>
165 swift 1.1 </table>
166    
167     <p>
168 jkt 1.9 If you have more than one DHCP client installed, you need to specify which one
169 jkt 1.10 to use - otherwise we default to <c>dhcpcd</c> if available.
170 swift 1.1 </p>
171    
172     <p>
173 jkt 1.10 To send specific options to the DHCP module, use <c>module_eth0="..."</c>
174 flammie 1.17 <e>(change module to the DHCP module you're using - i.e. <c>dhcpcd_eth0</c>)</e>.
175 swift 1.1 </p>
176    
177     <p>
178     We try and make DHCP relatively agnostic - as such we support the following
179 jkt 1.10 commands using the <c>dhcp_eth0</c> variable. The default is not to set any of
180     them:
181 swift 1.1 </p>
182    
183     <ul>
184 jkt 1.10 <li><c>release</c> - releases the IP address for re-use</li>
185     <li><c>nodns</c> - don't overwrite <path>/etc/resolv.conf</path></li>
186     <li><c>nontp</c> - don't overwrite <path>/etc/ntp.conf</path></li>
187     <li><c>nonis</c> - don't overwrite <path>/etc/yp.conf</path></li>
188 swift 1.1 </ul>
189    
190     <pre caption="Sample DHCP configuration in /etc/conf.d/net">
191     <comment># Only needed if you have more than one DHCP module installed</comment>
192     modules=( "dhcpcd" )
193    
194     config_eth0=( "dhcp" )
195     dhcpcd_eth0="-t 10" <comment># Timeout after 10 seconds</comment>
196     dhcp_eth0="release nodns nontp nonis" <comment># Only get an address</comment>
197     </pre>
198    
199     <note>
200 jkt 1.10 <c>dhcpcd</c>, <c>udhcpc</c> and <c>pump</c> send the current hostname to the
201     DHCP server by default so you don't need to specify this anymore.
202 swift 1.1 </note>
203    
204     </body>
205     </section>
206     <section>
207 nightmorph 1.23 <title>ADSL with PPPoE/PPPoA</title>
208 swift 1.1 <body>
209    
210     <p>
211     First we need to install the ADSL software.
212     </p>
213    
214 nightmorph 1.22 <pre caption="Install the ppp package">
215     # <i>emerge net-dialup/ppp</i>
216 swift 1.1 </pre>
217    
218 nightmorph 1.22 <note>
219 nightmorph 1.23 If you need PPPoA, then make sure to use >=<c>baselayout-1.12.x</c>.
220 nightmorph 1.22 </note>
221    
222     <p>
223 nightmorph 1.23 Second, create the PPP net script and the net script for the ethernet interface
224     to be used by PPP:
225 nightmorph 1.22 </p>
226    
227 nightmorph 1.23 <pre caption="Creating the PPP and ethernet scripts">
228 nightmorph 1.22 # <i>ln -s /etc/init.d/net.lo /etc/init.d/net.ppp0</i>
229 nightmorph 1.23 # <i>ln -s /etc/init.d/net.lo /etc/init.d/net.eth0</i>
230 nightmorph 1.22 </pre>
231 swift 1.1
232     <p>
233 nightmorph 1.23 Be sure to set RC_NET_STRICT_CHECKING="yes" in <path>/etc/conf.d/rc</path>.
234     </p>
235    
236     <p>
237 nightmorph 1.22 Now we need to configure <path>/etc/conf.d/net</path>.
238 swift 1.1 </p>
239    
240 nightmorph 1.22 <pre caption="A basic PPPoE setup">
241 nightmorph 1.23 config_eth0=( null ) <comment>(Specify your ethernet interface)</comment>
242 nightmorph 1.22 config_ppp0=( "ppp" )
243 nightmorph 1.23 link_ppp0="eth0" <comment>(Specify your ethernet interface)</comment>
244 nightmorph 1.22 plugins_ppp0=( "pppoe" )
245     username_ppp0='user'
246     password_ppp0='password'
247 nightmorph 1.23 pppd_ppp0=(
248     "noauth"
249     "defaultroute"
250     "usepeerdns"
251     "holdoff 3"
252     "child-timeout 60"
253     "lcp-echo-interval 15"
254     "lcp-echo-failure 3"
255     noaccomp noccp nobsdcomp nodeflate nopcomp novj novjccomp
256     )
257    
258     depend_ppp0() {
259     need net.eth0
260     }
261 swift 1.1 </pre>
262    
263     <p>
264 nightmorph 1.22 You can also set your password in <path>/etc/ppp/pap-secrets</path>.
265 swift 1.1 </p>
266    
267 nightmorph 1.22 <pre caption="Sample /etc/ppp/pap-secrets">
268 swift 1.1 <comment># The * is important</comment>
269 swift 1.4 "username" * "password"
270 swift 1.1 </pre>
271    
272 nightmorph 1.23 <p>
273     If you use PPPoE with a USB modem you'll need to emerge <c>br2684ctl</c>. Please
274     read <path>/usr/portage/net-dialup/speedtouch-usb/files/README</path> for
275     information on how to properly configure it.
276     </p>
277    
278 nightmorph 1.22 <impo>
279     Please carefully read the section on ADSL and PPP in
280     <path>/etc/conf.d/net.example</path>. It contains many more detailed
281     explanations of all the settings your particular PPP setup will likely need.
282     </impo>
283    
284 swift 1.1 </body>
285     </section>
286     <section id="apipa">
287     <title>APIPA (Automatic Private IP Addressing)</title>
288     <body>
289    
290     <p>
291 jkt 1.9 APIPA tries to find a free address in the range 169.254.0.0-169.254.255.255 by
292     arping a random address in that range on the interface. If no reply is found
293     then we assign that address to the interface.
294 swift 1.1 </p>
295    
296     <p>
297 jkt 1.9 This is only useful for LANs where there is no DHCP server and you don't connect
298     directly to the internet and all other computers use APIPA.
299 swift 1.1 </p>
300    
301     <p>
302 jkt 1.10 For APIPA support, emerge <c>net-misc/iputils</c> or <c>net-analyzer/arping</c>.
303 swift 1.1 </p>
304    
305     <pre caption="APIPA configuration in /etc/conf.d/net">
306     <comment># Try DHCP first - if that fails then fallback to APIPA</comment>
307     config_eth0=( "dhcp" )
308     fallback_eth0=( "apipa" )
309    
310     <comment># Just use APIPA</comment>
311     config_eth0=( "apipa" )
312     </pre>
313    
314     </body>
315     </section>
316     <section>
317     <title>Bonding</title>
318     <body>
319    
320     <p>
321 jkt 1.10 For link bonding/trunking emerge <c>net-misc/ifenslave</c>.
322 swift 1.1 </p>
323    
324     <p>
325 jkt 1.9 Bonding is used to increase network bandwidth. If you have two network cards
326     going to the same network, you can bond them together so your applications see
327     just one interface but they really use both network cards.
328 swift 1.1 </p>
329    
330     <pre caption="bonding configuration in /etc/conf.d/net">
331 jkt 1.13 <comment># To bond interfaces together</comment>
332 swift 1.1 slaves_bond0="eth0 eth1 eth2"
333    
334     <comment># You may not want to assign an IP to the bonded interface</comment>
335     config_bond0=( "null" )
336    
337     <comment># Depend on eth0, eth1 and eth2 as they may require extra configuration</comment>
338     depend_bond0() {
339 swift 1.4 need net.eth0 net.eth1 net.eth2
340 swift 1.1 }
341     </pre>
342    
343     </body>
344     </section>
345     <section>
346     <title>Bridging (802.1d support)</title>
347     <body>
348    
349     <p>
350 jkt 1.10 For bridging support emerge <c>net-misc/bridge-utils</c>.
351 swift 1.1 </p>
352    
353     <p>
354 jkt 1.9 Bridging is used to join networks together. For example, you may have a server
355     that connects to the internet via an ADSL modem and a wireless access card to
356     enable other computers to connect to the internet via the ADSL modem. You could
357     create a bridge to join the two interfaces together.
358 swift 1.1 </p>
359    
360     <pre caption="Bridge configuration in /etc/conf.d/net">
361 nightmorph 1.24 <comment># Configure the bridge - "man brctl" for more details</comment>
362 swift 1.1 brctl_br0=( "setfd 0" "sethello 0" "stp off" )
363    
364     <comment># To add ports to bridge br0</comment>
365     bridge_br0="eth0 eth1"
366    
367     <comment># You need to configure the ports to null values so dhcp does not get started</comment>
368     config_eth0=( "null" )
369     config_eth1=( "null" )
370    
371     <comment># Finally give the bridge an address - you could use DHCP as well</comment>
372     config_br0=( "192.168.0.1/24" )
373    
374     <comment># Depend on eth0 and eth1 as they may require extra configuration</comment>
375     depend_br0() {
376 swift 1.4 need net.eth0 net.eth1
377 swift 1.1 }
378     </pre>
379    
380     <impo>
381 jkt 1.10 For using some bridge setups, you may need to consult the <uri
382     link="?part=4&amp;chap=2#variable_name">variable name</uri> documentation.
383 swift 1.1 </impo>
384    
385     </body>
386     </section>
387     <section>
388     <title>MAC Address</title>
389     <body>
390    
391     <p>
392 rane 1.11 You don't need to emerge anything for changing the MAC address of your
393     interface if you have <c>sys-apps/baselayout-1.11.14</c> or newer and want to
394 fox2mike 1.12 change to a specific MAC address. However, if you need to change to a random MAC
395     address or have a baselayout older than the version mentioned above, you have
396     to emerge <c>net-analyzer/macchanger</c> to be able to make use of this feature.
397 swift 1.1 </p>
398    
399     <pre caption="MAC Address change example">
400     <comment># To set the MAC address of the interface</comment>
401     mac_eth0="00:11:22:33:44:55"
402    
403     <comment># To randomize the last 3 bytes only</comment>
404     mac_eth0="random-ending"
405    
406 flammie 1.17 <comment># To randomize between the same physical type of connection (e.g. fibre,
407 swift 1.1 # copper, wireless) , all vendors</comment>
408     mac_eth0="random-samekind"
409    
410 flammie 1.17 <comment># To randomize between any physical type of connection (e.g. fibre, copper,
411 swift 1.1 # wireless) , all vendors</comment>
412     mac_eth0="random-anykind"
413    
414     <comment># Full randomization - WARNING: some MAC addresses generated by this may
415     # NOT act as expected</comment>
416     mac_eth0="random-full"
417     </pre>
418    
419     </body>
420     </section>
421     <section>
422     <title>Tunnelling</title>
423     <body>
424    
425     <p>
426 jkt 1.9 You don't need to emerge anything for tunnelling as the interface handler can do
427     it for you.
428 swift 1.1 </p>
429    
430     <pre caption="Tunnelling configuration in /etc/conf.d/net">
431     <comment># For GRE tunnels</comment>
432     iptunnel_vpn0="mode gre remote 207.170.82.1 key 0xffffffff ttl 255"
433    
434     <comment># For IPIP tunnels</comment>
435     iptunnel_vpn0="mode ipip remote 207.170.82.2 ttl 255"
436    
437     <comment># To configure the interface</comment>
438     config_vpn0=( "192.168.0.2 peer 192.168.1.1" )
439     </pre>
440    
441     </body>
442     </section>
443     <section>
444     <title>VLAN (802.1q support)</title>
445     <body>
446    
447     <p>
448 jkt 1.10 For VLAN support, emerge <c>net-misc/vconfig</c>.
449 swift 1.1 </p>
450    
451 swift 1.2 <p>
452 jkt 1.9 Virtual LAN is a group of network devices that behave as if they were connected
453     to a single network segment - even though they may not be. VLAN members can only
454     see members of the same VLAN even though they may share the same physical
455     network.
456 swift 1.1 </p>
457    
458     <pre caption="VLAN configuration in /etc/conf.d/net">
459     <comment># Specify the VLAN numbers for the interface like so</comment>
460     <comment># Please ensure your VLAN IDs are NOT zero-padded</comment>
461     vlans_eth0="1 2"
462    
463     <comment># You can also configure the VLAN</comment>
464     <comment># see for vconfig man page for more details</comment>
465     vconfig_eth0=( "set_name_type VLAN_PLUS_VID_NO_PAD" )
466     vconfig_vlan1=( "set_flag 1" "set_egress_map 2 6" )
467    
468     <comment># Configure the interface as usual</comment>
469     config_vlan1=( "172.16.3.1 netmask 255.255.254.0" )
470     config_vlan2=( "172.16.2.1 netmask 255.255.254.0" )
471     </pre>
472    
473     <impo>
474 jkt 1.10 For using some VLAN setups, you may need to consult the <uri
475     link="?part=4&amp;chap=2#variable_name">variable name</uri> documentation.
476 swift 1.1 </impo>
477    
478     </body>
479     </section>
480    
481     </sections>

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