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Chris Brennan wrote: |
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> I am trying to set up a Bridge for Qemu to use. I followed the guide |
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> at |
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> http://gentoo-wiki.com/HOWTO:_Qemu#Using_TUN.2FTAP_interface_as_a_normal_user |
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> but when ever the bridge starts, I loose connectivity outside of my |
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> box :/ ... am I missing something .... |
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> |
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> |
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> I've includes the output of my /etc/conf.d/net file .... |
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... |
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> ## |
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> # LAN |
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> ## |
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> config_eth0=( "192.168.1.2 netmask 255.255.255.0 brd 192.168.1.255" ) |
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> routes_eth0=( "default via 192.168.1.1" ) |
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> |
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> ## |
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> # Bridge |
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> ## |
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> bridge_br0="eth0" |
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> config_br0=( "192.168.1.20 netmask 255.255.255.0 brd 192.168.1.255" ) |
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> #dhcpcd_br0="-t 10" |
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> RC_NEED_br0="net.eth0" |
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> brctl_br0=( "setfd 0" "sethello 0" "stp off" ) |
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> config_tap0=( "10.0.2.1 netmask 255.255.255.0" ) |
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> |
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|
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Here's my /etc/conf.d/net for bridging. |
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|
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# Begin ############################################################## |
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# dynamically add devs to br0 as they are created |
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bridge_add_tap0="br0" |
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bridge_add_tap1="br0" |
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bridge_add_tap2="br0" |
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|
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# put devs in promiscuous mode, br0 has config |
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config_eth0=( "0.0.0.0 promisc" ) |
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config_tap0=( "0.0.0.0 promisc" ) |
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config_tap1=( "0.0.0.0 promisc" ) |
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config_tap2=( "0.0.0.0 promisc" ) |
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|
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config_br0=( "192.168.1.2 netmask 255.255.255.0" ) |
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routes_br0=( "default via 192.168.1.1" ) |
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bridge_br0="eth0" |
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|
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# cascading deps tap* irrelevant w/o br0 and eth0 |
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depend_tap0() { |
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need net.br0 |
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} |
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depend_tap1() { |
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need net.br0 |
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} |
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depend_tap2() { |
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need net.br0 |
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} |
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depend_br0() { |
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need net.eth0 |
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} |
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|
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# enable proxyarping |
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postup() { |
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if [[ ${IFACE} == "tap0" ]] ; then |
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echo " * Enabling Proxy ARP on ${IFACE}..." |
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echo 1 >/proc/sys/net/ipv4/conf/tap0/proxy_arp |
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fi |
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if [[ ${IFACE} == "tap1" ]] ; then |
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echo " * Enabling Proxy ARP on ${IFACE}..." |
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echo 1 >/proc/sys/net/ipv4/conf/tap1/proxy_arp |
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fi |
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|
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} |
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|
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# remove from bridge |
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postdown() { |
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if [[ ${IFACE} == "tap0" ]] ; then |
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echo " * Removing ${IFACE} from bridge br0..." |
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brctl delif br0 tap0 |
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echo " * Disabling Proxy ARP on ${IFACE}..." |
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echo 0 >/proc/sys/net/ipv4/conf/tap0/proxy_arp |
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fi |
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if [[ ${IFACE} == "tap1" ]] ; then |
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echo " * Removing ${IFACE} from bridge br0..." |
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brctl delif br0 tap1 |
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echo " * Disabling Proxy ARP on ${IFACE}..." |
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echo 0 >/proc/sys/net/ipv4/conf/tap1/proxy_arp |
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fi |
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|
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} |
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# End ################################################################ |
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|
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The key difference is that the underlying "real" devices in the bridge |
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need to be 0.0.0.0 and in promiscuous mode. The bridge has the ip |
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address. |
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|
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If you _need_ two separate subnets, you may want to use a tun and |
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iptables or ip_forward/route. One idea you might try is what I |
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suggested, but with br0 = subnetA, br0:1 = subnetB... Not sure it would |
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work, but worth a try. |
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|
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Assuming your tap device is the end of an incoming VPN, the proxy arping |
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is only necessary if you want the VPN client (the above script is for |
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the VPN server) to be able to hit the internet through the server's gateway. |
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|
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Yeah, looking at the preup/postdown functions just now made me realize I |
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wrote them a _long_ time ago. rewrite at your leisure... ;-) |
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|
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hth, |
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|
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Jason. |
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-- |
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