Já pensou em configurar uma redundância entre uma interface ethernet (eth0) e uma wireless (wlan0)? Aqui você aprenderá como.
Usei o CentOS 5.6 como sistema operacional, mas o procedimento funciona em toda a família CentOS.
Primeiro devemos baixar o módulo wireless para o sistema:
<br />
wget http://elrepo.org/linux/elrepo/el5/i386/RPMS/iwl5000-firmware-8.24.2.12-1.elrepo.noarch.rpm<br />
E instalar
<br />
rpm -Uvh iwl5000-firmware-8.24.2.12-1.elrepo.noarch.rpm<br />
Agora vamos configurar a interface bond0
<br />
[root@zimbaro10 ~]# cd /etc/sysconfig/network-scripts/<br />
[root@zimbaro10 network-scripts]# cat ifcfg-bond0<br />
DEVICE=bond0<br />
#IPADDR=192.168.0.10<br />
#NETWORK=192.168.0.0<br />
#NETMASK=255.255.255.0<br />
USERCTL=no<br />
BOOTPROTO=none<br />
ONBOOT=yes<br />
BOOTPROTO=dhcp<br />
Aqui configuraremos a interface ethernet
<br />
[root@zimbaro10 network-scripts]# cat ifcfg-eth0<br />
# Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller<br />
DEVICE=eth0<br />
USERCTL=no<br />
ONBOOT=yes<br />
MASTER=bond0<br />
SLAVE=yes<br />
BOOTPROTO=none<br />
E a interface wireless
<br />
[root@zimbaro10 network-scripts]# cat ifcfg-wlan0<br />
# Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller<br />
DEVICE=wlan0<br />
USERCTL=no<br />
ONBOOT=yes<br />
MASTER=bond0<br />
SLAVE=yes<br />
#BOOTPROTO=dhcp<br />
TYPE=WIRELESS<br />
WLAN_ESSID[4]="Zimbaronet2"<br />
WLAN_WPA[4]="wpa_supplicant"<br />
WLAN_WPADRIVER[4]="wext"<br />
Agora devemos criar um script para inicialização do módulo
<br />
[root@zimbaro10 network-scripts]# cat /root/scripts/run_wpa.sh<br />
#!/bin/bash
<br />
wpa_supplicant -Dwext -iwlan0 -c/etc/wpa_supplicant.conf &
exit 0
E iniciarmos no boot inserindo o comando no rc.local
<br />
[root@zimbaro10 network-scripts]# cat /etc/rc.local<br />
#!/bin/sh<br />
#<br />
# This script will be executed *after* all the other init scripts.<br />
# You can put your own initialization stuff in here if you don't<br />
# want to do the full Sys V style init stuff.
<br />
touch /var/lock/subsys/local
chown szimbaro:gammu /dev/ttyACM0
sh /root/scripts/run_wpa.sh
Agora vamos as configurações do bonding. Altere o parâmetro mode de acordo com a sua preferência (veja aqui as opções).
<br />
[root@zimbaro10 network-scripts]# cat /etc/modprobe.d/bonding.conf<br />
alias bond0 bonding<br />
options bond0 mode=0 miimon=100 updelay=200 downdelay=200<br />
E inicialização do módulo
<br />
[root@zimbaro10 network-scripts]# modprobe bonding<br />
Aqui temos a configuração do wpa_supplicant para o módulo wireless.
<br />
[root@zimbaro10 network-scripts]# cat /etc/wpa_supplicant.conf<br />
ctrl_interface=/var/run/wpa_supplicant<br />
#ap_scan=2
<br />
network={<br />
ssid="Zimbaronet2"<br />
scan_ssid=1<br />
proto=WPA RSN<br />
key_mgmt=WPA-PSK<br />
pairwise=CCMP TKIP<br />
group=CCMP TKIP<br />
psk=57684e9c880c915c065c4653f2bb8d5cb2e59d0ccab1319a45e9f9e73ab5a763<br />
}<br />
O código psk acim foi gerado com base no SSID e senha da sua rede wireless
<br />
[root@zimbaro10 network-scripts]# wpa_passphrase Zimbaronet2 senharedewifi<br />
Agora podemos reiniciar o sistema. As configurações de interface devem ficar assim:
<br />
[root@zimbaro10 network-scripts]# ifconfig<br />
bond0 Link encap:Ethernet HWaddr 00:22:64:4D:22:CA<br />
inet addr:192.168.0.10 Bcast:192.168.0.255 Mask:255.255.255.0<br />
inet6 addr: fe80::222:64ff:fe4d:22ca/64 Scope:Link<br />
UP BROADCAST RUNNING MASTER MULTICAST MTU:1500 Metric:1<br />
RX packets:3283 errors:0 dropped:0 overruns:0 frame:0<br />
TX packets:2118 errors:0 dropped:0 overruns:0 carrier:0<br />
collisions:0 txqueuelen:0<br />
RX bytes:351568 (343.3 KiB) TX bytes:383828 (374.8 KiB)
<br />
eth0 Link encap:Ethernet HWaddr 00:22:64:4D:22:CA<br />
UP BROADCAST RUNNING SLAVE MULTICAST MTU:1500 Metric:1<br />
RX packets:1026 errors:0 dropped:0 overruns:0 frame:0<br />
TX packets:1066 errors:0 dropped:0 overruns:0 carrier:0<br />
collisions:0 txqueuelen:1000<br />
RX bytes:99420 (97.0 KiB) TX bytes:175135 (171.0 KiB)<br />
Interrupt:177 Base address:0xa000
<br />
lo Link encap:Local Loopback<br />
inet addr:127.0.0.1 Mask:255.0.0.0<br />
inet6 addr: ::1/128 Scope:Host<br />
UP LOOPBACK RUNNING MTU:16436 Metric:1<br />
RX packets:113 errors:0 dropped:0 overruns:0 frame:0<br />
TX packets:113 errors:0 dropped:0 overruns:0 carrier:0<br />
collisions:0 txqueuelen:0<br />
RX bytes:23981 (23.4 KiB) TX bytes:23981 (23.4 KiB)<br />
<br />
wlan0 Link encap:Ethernet HWaddr 00:22:64:4D:22:CA<br />
UP BROADCAST RUNNING SLAVE MULTICAST MTU:1500 Metric:1<br />
RX packets:2257 errors:0 dropped:0 overruns:0 frame:0<br />
TX packets:1054 errors:0 dropped:0 overruns:0 carrier:0<br />
collisions:0 txqueuelen:1000<br />
RX bytes:252148 (246.2 KiB) TX bytes:209769 (204.8 KiB)<br />
[root@zimbaro10 network-scripts]#<br />
É isso!