# strange veth (virtual eth pair) behaviour - no arp response

## matrix47

Hello!

I can't seem to get to work a virtual ethernet device pair (veth).

Can anyone explain to me why this simple configuration does not work?

Setting up veth device pair and configuring interfaces:

```
ip link add veth.0 type veth peer name veth.1

ifconfig veth.0 10.0.0.1/24

ifconfig veth.1 10.0.0.2/24
```

Put simple ping does not work!

```
ping -I veth.0 10.0.0.2

PING 10.0.0.2 (10.0.0.2) from 10.0.0.1 veth.0: 56(84) bytes of data.

From 10.0.0.1: icmp_seq=1 Destination Host Unreachable

From 10.0.0.1: icmp_seq=2 Destination Host Unreachable

From 10.0.0.1: icmp_seq=3 Destination Host Unreachable

From 10.0.0.1: icmp_seq=4 Destination Host Unreachable

From 10.0.0.1: icmp_seq=5 Destination Host Unreachable

From 10.0.0.1: icmp_seq=6 Destination Host Unreachable
```

Though there is activity on veth.1 interface while pinging:

```
tcpdump -i veth.1

tcpdump: verbose output suppressed, use -v or -vv for full protocol decode

listening on veth.1, link-type EN10MB (Ethernet), capture size 65535 bytes

17:47:46.554759 ARP, Request who-has 10.0.0.2 tell 10.0.0.1, length 28

17:47:47.556776 ARP, Request who-has 10.0.0.2 tell 10.0.0.1, length 28

17:47:49.555119 ARP, Request who-has 10.0.0.2 tell 10.0.0.1, length 28

17:47:50.556749 ARP, Request who-has 10.0.0.2 tell 10.0.0.1, length 28
```

I bumbed into this wile investigating for another issue: https://forums.gentoo.org/viewtopic-t-939778.html

----------

## DONAHUE

https://forums.gentoo.org/viewtopic-p-7164550.html?sid=411b98cdaf63307e94a5cc38bed583cf

http://www.gentoo.org/doc/en/handbook/handbook-amd64.xml?style=printable&full=1#book_part4_chap3

----------

