A customer appears to have drastically misunderstood our instructions for connecting to our WAN. He set his PC IP address to the same as one of the bridges. This caused much confusion on the network, to put it mildly. He called to complain about the poor performance of the network he ruined, then made himself unavailable for phone calls so it couldn't be fixed.
Even blocking his MAC address didn't help. The bridging problem happens in midair, nowhere the server can control. If I could at least get into the bridge, I could reconfigure it to a different IP and allow traffic again...
So, on the server, I tried this:
This succeeded in forcing the server to talk to the bridge, not to him. I was then able to get into the bridge's web interface and change its IP from there. From there it was easy.
These 5 Users Gave Thanks to Corona688 For This Post:
How does ARP take care of uniqueness of physical addresses?
How does an ISP allocate a MAC address when I do not have an NIC( Network interface Card)? (1 Reply)
Dear all,
We are testing two of our servers for mq series connectivity. The scenario is, when one machine is shutting down it's services there are some scripts that do a dns update, which removes the ip address and relates it to the ip address of the other node on our dns server, and the update... (7 Replies)
Does ARP Request packet Contains MAC Address of dest during broadcast?
I found It So...
When i captured ARP Req Pkts on ethereal...
Rgds
-Meti (1 Reply)
I was checking nettl output for a unstable telnet to my server. this is part of output:
###
***********************************STREAMS/UX*******************************@#%
Timestamp : Sun Jun 22 EETDST 2008 22:14:47.492899
Process ID : Subsystem ... (4 Replies)
I'm running an arp -an on a Solaris 10 box. We're using IPMP. One of the systems is not able to see a host on the same network. The only difference between the two systems (one is having a problem, the other isn't) at least so far is the output of arp:
# arp -an | grep 224.55
e1000g5... (1 Reply)
Dear All
i have a linux proxy server which has RHEL-5 64 bit, it has two interfaces, it has the following details
eth0=10.200.14.42
eth3=10.201.14.42
default gateway=10.201.14.254
one static route=192.168.0.0/24 gw 10.200.14.254
i am facing a problem when i ping 10.201.14.42 from... (2 Replies)
About a week ago a customer hooked up a wireless router backwards to our network, causing it to serve incorrect DHCP addresses to some of them. Our networks are mostly statically assigned so this didn't cause as much damage as it might have, but now, over a week later, I still have incomplete... (1 Reply)
Can someone please explain this output to me. Why doesn't ifconfig show the same info?
~ $ arp -a
? (10.71.0.1) at 00:1b:21:2b:eb:0c on eth0 (4 Replies)
Hi, I'm trying to find a way to protect my network against arp spoofing.
What it is:
An attacker sends fake arp packets in the network, identifying himself as the router. All network traffic is then redirected to this attacker.
How to protect myself:
In my opinion, the best possible... (2 Replies)
Hello,
I have 2 clients with Unix installed.
host1: eth0 (192.168.5.10) & eth1 (192.168.10.10)
host2: eth0 (192.168.10.20)
I've connected host1-eth1 to host2-eth0. host1-eth0 isn't connected.
I started 'tcpdump' on wonder that host2 got ARP requests for 192.168.5.10.
Any idea why host1... (2 Replies)
Discussion started by: daWonderer
2 Replies
LEARN ABOUT DEBIAN
net::arp
ARP(3pm) User Contributed Perl Documentation ARP(3pm)NAME
ARP - Perl extension for creating ARP packets
SYNOPSIS
use Net::ARP;
Net::ARP::send_packet('lo', # Device
'127.0.0.1', # Source IP
'127.0.0.1', # Destination IP
'aa:bb:cc:aa:bb:cc', # Source MAC
'aa:bb:cc:aa:bb:cc', # Destinaton MAC
'reply'); # ARP operation
$mac = Net::ARP::get_mac("eth0");
print "$mac
";
$mac = Net::ARP::arp_lookup($dev,"192.168.1.1");
print "192.168.1.1 has got mac $mac
";
IMPORTANT
Version 1.0 will break with the API of PRE-1.0 versions, because the return value of arp_lookup() and get_mac() will no longer be passed as
parameter, but returned! I hope this decision is ok as long as we get a cleaner and more perlish API.
DESCRIPTION
This module can be used to create and send ARP packets and to get the mac address of an ethernet interface or ip address.
send_packet()
Net::ARP::send_packet('lo', # Device
'127.0.0.1', # Source IP
'127.0.0.1', # Destination IP
'aa:bb:cc:aa:bb:cc', # Source MAC
'aa:bb:cc:aa:bb:cc', # Destinaton MAC
'reply'); # ARP operation
I think this is self documentating.
ARP operation can be one of the following values:
request, reply, revrequest, revreply, invrequest, invreply.
The default ARP operation is reply.
get_mac()
$mac = Net::ARP::get_mac("eth0");
This gets the MAC address of the eth0 interface and stores
it in the variable $mac. The return value is "unknown" if
the mac cannot be looked up.
arp_lookup()
$mac = Net::ARP::arp_lookup($dev,"192.168.1.1");
This looks up the MAC address for the ip address 192.168.1.1
and stores it in the variable $mac. The return value is
"unknown" if the mac cannot be looked up.
SEE ALSO
man -a arp
AUTHOR
Bastian Ballmann [ Balle@chaostal.de ]
http://www.datenterrorist.de
COPYRIGHT AND LICENSE
Copyright (C) 2004-2007 by Bastian Ballmann
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.1 or,
at your option, any later version of Perl 5 you may have available.
perl v5.14.2 2009-04-24 ARP(3pm)