11

Can anyone provide some information about the HW Type, and what the Flags mean, for the Arp command shown below?

root@OpenWrt:~# arp -x
IP address       HW type     Flags       HW address            Mask     Device
192.168.1.67     0x1         0x0         00:00:00:00:00:00     *        eth0.2
192.168.1.115    0x1         0x0         00:00:00:00:00:00     *        eth0.2
192.168.1.1      0x1         0x2         00:1f:90:XX:XX:XX     *        eth0.2
192.168.10.199   0x1         0x2         78:31:c1:XX:XX:XX     *        br-lan

I looked at Man on a Linux box (no Man on OpenWRT), but I can't seem to find it.

I gather 0x0 means "Incomplete", but wondering what the other flags could be and mean.

Ƭᴇcʜιᴇ007
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rainkinz
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1 Answers1

12

The flags indicate if the mac address has been learned, manually set, published (announced by another node than the requested) or is incomplete.

I think you can must check your kernel source to figure out what the flags mean or you simply try it. My system translates

  • 0x0 incomplete
  • 0x2 complete
  • 0x6 complete and manually set

Learned by comparing the output of arp with /proc/net/arp.

The definition of the flags is given in include/uapi/linux/if_arp.h.

user3422070
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