# Network interface stops working on addition of a bridge.

## dE_logics

First, create a tap interface -- 

```
ip tuntap add mode tap veth
```

Stop network manager

```
/etc/init.d/NetworkManager stop
```

down all interfaces -- 

```
ifconfig eth1 down

ifconfigh veth down
```

Add bridge -- 

```
brctl addbr eth1_veth
```

Bridge eth1 and veth -- 

```
brctl addif eth1_veth eth1 veth
```

run dhcpcd on eth1 -- 

```
dhcpcd[6316]: version 5.6.4 starting

dhcpcd[6316]: eth1: carrier lost

dhcpcd[6316]: eth1: carrier acquired

dhcpcd[6316]: eth1: sending IPv6 Router Solicitation

dhcpcd[6316]: eth1: sendmsg: Cannot assign requested address

dhcpcd[6316]: eth1: rebinding lease of 192.168.1.2

dhcpcd[6316]: eth1: sending IPv6 Router Solicitation

dhcpcd[6316]: eth1: broadcasting for a lease

dhcpcd[6316]: eth1: sending IPv6 Router Solicitation

dhcpcd[6316]: eth1: sending IPv6 Router Solicitation

dhcpcd[6316]: eth1: no IPv6 Routers available

dhcpcd[6316]: timed out

dhcpcd[6316]: allowing 8 seconds for IPv4LL timeout

dhcpcd[6316]: eth1: probing for an IPv4LL address

dhcpcd[6316]: eth1: checking for 169.254.229.90

dhcpcd[6316]: eth1: using IPv4LL address 169.254.229.90

dhcpcd[6316]: forked to background, child pid 6369
```

Note, 169.254.229.90 is unheard of in my LAN, so this's just a random IP address. The DHCP server (built in a route) is working fine for other node in the LAN.

```
ifconfig eth1_veth up
```

does not help. Networkmanager fails to configure the interface for dhcp.

Forcing a valid IP does work, but the interface can't do any communication to anything.

The moment I delete the bridge eth1_veth, everything starts working.

----------

## massimo

Check out Modular Networking. Further eth1 and veth should be up when you bring the bridge's link up. Why do you run dhcpcd against eth1 and not the bridge interface?

----------

## dE_logics

 *massimo wrote:*   

> Further eth1 and veth should be up when you bring the bridge's link up. Why do you run dhcpcd against eth1 and not the bridge interface?

 

Woah! I didn't know that! Thanks!

----------

