lkml.org 
[lkml]   [2001]   [Oct]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: how to see manually specified proxy arp entries using "ip neigh"
"Matthew G. Marsh" wrote:

> > Currently I have been doing this by manually setting proxy arping on the NIC for
> > the IP address assigned to the ethertap device. If this feature is going to be
> > removed, then how should I be doing this?
>
> If an IP address is routed to on the external network then it will be
> available. It does _not_ matter what interface that address is assigned
> to. EX:
>
> ip addr add 10.1.1.1/24 dev dummy0
> ip link set dev dummy0 up
>
> now ping 10.1.1.1 from another machine on eth0 that has an appropriate
> route. I suspect what is really biting you is that your rp_filters are way
> too restrictive on your machine.

Sorry, I guess I explained it wrong. Ethertap has an IP address assigned to the
device in the linux kernel. It is then configured with a point to point route
to another IP address on the other concepual end of the link (ie in userspace).
It is this other IP address that I am proxy arping for.

Thus,

[mtc@10.40.14.70 mtc]$ /sbin/ip add
<stuff removed>
4: tap0: <BROADCAST,MULTICAST,NOARP,UP> mtu 1500 qdisc noqueue
link/ether fe:fd:00:00:00:00 brd ff:ff:ff:ff:ff:ff
inet 10.40.14.73 peer 10.40.14.74/32 brd 10.40.14.255 scope global tap0

[mtc@10.40.14.70 mtc]$ /sbin/ip ro
10.40.14.74 dev tap0 proto kernel scope link src 10.40.14.73
<stuff removed>

[mtc@10.40.14.70 mtc]$ /sbin/arp
Address HWtype HWaddress Flags Mask Iface
<stuff removed
10.40.14.74 * * MP eth1


Thus, anyone arping for 10.40.14.74 (which is on top of a protocol stack in
userspace) will get the MAC address of eth1 as a response.

I cannot turn on proxy arping for the interface in general as I have eth0 and
eth1 on the same subnet and turning on proxy arping causes bad things to
happen. Thus I have a single manual proxy entry in the arp table.



--
Chris Friesen | MailStop: 043/33/F10
Nortel Networks | work: (613) 765-0557
3500 Carling Avenue | fax: (613) 765-2986
Nepean, ON K2H 8E9 Canada | email: cfriesen@nortelnetworks.com
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:08    [W:0.059 / U:1.088 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site