Address Resolution Protocol is a layer 2 networking protocol used for resolving layer 3 addresses (such as IP addresses) into layer 2 addresses (such as Ethernet MACs). It is used by network devices when communicating with devices on the same layer 2 network.

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Is it the normal behavior of arp requests?

Sometimes I dive into my network and often I see: tcpdump -n arp 17:59:15.754508 ARP, Request who-has 192.168.1.65 tell 192.168.1.212, length 28 17:59:16.754401 ARP, Request who-has 192.168.1.65 ...
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8answers
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Is there any way to ARP ping on Windows?

On Linux and other systems, there is an utility called arping which can be used to send ARP requests ("pings") and show the answers, much like the "ping" utility but using ARP instead of ICMP. Is ...
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1answer
2k views

How to setup a static multicast ARP entry with Cisco SG300?

We're running a Microsoft NLB cluster in multicast mode as a loadbalancer. Using our old Cisco IOS switches we propagate access to the cluster to our branches using a static ARP entry in the core ...
0
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1answer
155 views

Cisco ASA 5510 needs “clear arp <Interface>” periodically to reach a single host

ASA 9.0(3) The symptom is that I can ping from the ASA to any other host in that interface's subnet, save one particular host (that host can ping the interface on the ASA however). If I do "clear arp ...
0
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1answer
33 views

How to reverse arp using nping for Windows

I would like to send a reverse ARP to resolve an IP address given a MAC address using nping for Windows. The documentation is not clear on how this should work and I'm unable to find any examples ...
4
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1answer
1k views

ARP reply vanishes from br0 to tap0 using OpenVPN in bridging mode

i have setup a linux box (on an esxi5) which acts as an openvpn server. the server is configured to use bridging for the clients, which essentially works, with one exception. if the client pings some ...
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6answers
17k views

Is it possible to match an internal IP address to a switch port?

I'm trying to find a computer that has a certain IP address on our internal network. I have identified the computer name from DNS, but in this case it does not help me. Just wondering if I can ...
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1answer
54 views

First Reply on Ping is Unreachable the rest is okay [closed]

please check this weird ping i'm having What may have caused this problem
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1answer
134 views

VMXNET3 nic loses the ability to update ARP table after N hours

I have a fedora 18 VM that stops updating the arp table on eth1 after running for a number of hours to days. There are other VMs on the same hypervisor that can access all of the same networks without ...
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4answers
59 views

Fault tolerance by using two IP with two interfaces

I would like to have a fault-tolerant setup for http requests. For brevity, let's assume we have a very simple Web-service and there is no difference which server responses. So I will have the ...
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0answers
87 views

KVM Windows guest macvtap host device bridge no access to network but DHCP works

KVM on CentOS 7, guest OS windows 7 x64, I need the guest to have direct access to network and let my network infrastructure to handle IP addressing. In virt-manager, I set NIC to: source device => ...
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0answers
29 views

arp poisoning and mitm protection [closed]

I'm trying to understand mitm by arp poisoning. To do so I'm practicing on the network I manage: attacker : IPA victim : IPC gateway : IPG I use nighthawk, and kali linux (via virtual box). I can ...
1
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1answer
62 views

How to troubleshoot internet unreachable periodically through firewall

Periodically the internet is unreachable on my network, sometimes for 30+ minutes. After testing a direct connection to our modem, I realized this was not a problem with our ISP but the network ...
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6answers
9k views

ARP replies contain wrong MAC address

I've got a robot running linux with wired and wireless adapters. When I boot up, it connects to the wireless fine. When I assign an IP to the wired (either statically or with DHCP), it looks like it ...
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2answers
186 views

Linux is sending ARP requests to hosts in other subnets?

Setup Host B <--> Router <--> Host A Host A: IP = 192.168.1.10, Net = 192.168.1.0/24, VLAN = 1, Default GW = 192.168.1.1 (Router) Host B: IP = 192.168.2.10, Net = 192.168.2.0/24, VLAN ...
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3answers
2k views

Linux machine does not answer an ARP request

We have this situation: A router, which is an Ubuntu VM, has multiple VLAN interfaces on the same physical NIC. Those VLAN interfaces are dynamically configured and torn down and attached to networks ...
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0answers
84 views

Linux bridge not answering arp packets

I'm trying to setup a test scenario regarding linux bridges for which I need a full virtual IP stack. Basically, I'd like to simulate the network between a VM (or container) and its host, just without ...
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0answers
66 views

linux not replying to an arp request

I am running linux 3.14 on a system with 2 interfaces. on the first interface, i can access our local network. on the second interface, arp packets come in but linux doesn't send out reply. is it ...
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2answers
250 views

How is a TCP request routed from a virtual machine to an outside resource and back again?

Scenario: Computer A has a local ip of 192.168.1.100, which is running a VM inside of it. The VM now makes a tcp request to an external IP address (74.125.225.98). Could someone explain how the ...
0
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1answer
52 views

iptables: service per physical interface

I have a vm on which I'm trying to configure (unsuccessfully) one service per physical device - i.e. ssh open only on eth0, http only on eth1 and ftp only on eth2. This has to happen regardless on the ...
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1answer
174 views

How does Bind IP to MAC work? [closed]

A client is connected to the network with a DHCP server, but also has a Bind IP to MAC entry in the router. What is the sequence of steps that determine the final client IP configuration given that ...
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2answers
83 views

Why am I not getting an ARP reply with this request?

Using pcap_sendpacket in C, I'm manually sending the following packet on wlan0 (I've left out some fields, but I think they are correct): (Ethernet layer) eth src: <wlan0 MAC address> eth ...
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0answers
30 views

How to meet the arp table and the network toology with wireshark

I'm wondering if is possible meet(see) the arp table in a network traffic with wireshark or find some way to build manually the arp table, and how to see the router and swiches of topology( for ...
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1answer
2k views

ARP response is not present on the other port of linux bridge based on ubuntu 13.10

I recently build linux based bridge for packet monitoring purpose, but there is BIG problem. the environment is, overall env. target of monitoring is VMs on vSphere. two vSwitches are configured ...
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2answers
1k views

Multiple NIC arp issue

I'm troubleshooting an issue on Centos 6.4. I have a few systems setting up for greenplum. Each one has two "interconnect" interfaces connecting to an isolated subnet. It is like a cluster ...
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0answers
112 views

Broadcom NICs, Cisco ASA and ARP request collisions

First of all I am sorry for my english mistakes. Help me please to solve the problem with ARP request collision incidents. I have IBM BladeCenter E chasis with blade servers are installed in this ...
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0answers
57 views

FreeBSD jail loses network connectivity after some time

I have a Jail on a FreeBSD 9.2 installation on my office network, which I use to run some cron jobs that upload and download stuff from external servers. The cron jobs are configured on the main ...
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0answers
82 views

Pinging two virtual interfaces(IP aliasing) not working

I have two VMs. I have created a virtual interface on each of the VMs. On VM1: eth0 Link encap:Ethernet HWaddr 06:98:82:00:00:39 inet addr:10.129.34.76 Bcast:10.129.255.255 ...
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votes
2answers
4k views

how can I stop my sonicwall TZ-210 (SonicOS Enhanced 5.5.1.0-5o) from responding to arp queries on the wan subnet?

My sonicwall TZ-210 is answering arp queries on the wan subnet (which my isp doesn't like), basically mapping all the wan ips to its own mac address, causing network havoc since it is not set to route ...
0
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2answers
189 views

External ip address being treated as local (ARP asking for external IP's address)

I am using a virtual machine with OpenWRT for routing, on a Linux machine (Slackware). I am trying to configure a host only interface (eth0) as the wan interface. eth1 is Ethernet attached as a bridge ...
0
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1answer
82 views

How can I tell what's happening to my packets?

I'm trying to bring up a little box on my network. I just reflashed the firmware and it's supposed to come up as 192.168.1.1 by default. My router is a DSL modem at 192.168.0.1; it usually uses a ...
4
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1answer
4k views

Why ARP request is unicast?

I have a wireshark capture that indicating a unicast ARP request from source to destination. As per my understanding ARP requests (including gratutious ARP) use broadcast. In what case the ...
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0answers
257 views

VMWare use of Gratuitous ARP REPLY

I have an ESXi cluster that hosts several Windows Server VMs and around 30 Windows workstation VMs. Packet captures show a high number of ARP replies of the form: -sender_ip: VM IP -sender_mac: VM ...
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1answer
596 views

arp problems with transparent bridge on linux

I've been trying to secure my virtual machines on my esx server by putting them behind a transparent bridge with 2 interfaces, one in front, one at the back. My intention is to put all the firewall ...
2
votes
2answers
2k views

How can I configure permanent arp entries on Red Hat Enterprise Linux?

I'm configuring a Red Hat Linux server which will be sending UDP packets out but never receiving ARP responses. So a static ARP entry is required. The obvious way to do this is. arp -s 10.0.0.1 ...
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0answers
47 views

How to fix stalled connection on large download

I have a cisco 1921 router performing routing and NAT function. Cisco 3750 is performing layer 3 core switching duties. Users are complaining about large file transfers being stalled (not dropped) ...
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1answer
146 views

Directed ARP requests do not arrive at bridge interface

I'm baffled by the following weird bridge/arp behavior under Linux. It somehow seems to filter directed ARP requests, whereas it should forward them to the other end of the bridge. To test, I run the ...
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2answers
126 views

Windows 8 is not always selecting correct network card for my outgoing transmissions

The company I work for builds and sells industrial machines. One of our products is a machine which is controlled by a PC running Windows. This particular machine uses a networked device with ...
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0answers
90 views

X520-DA2 10GbE PCIe NIC on Ubuntu 12.04 doesn't respond correct ARP information for a traffic tester

I'm trying to configure stand-alone test network to examine a server that has two 10GbE ports PCIe NIC. But I couldn't get any ARP responses of those 10GbE ports. To execute my test, it's necessary to ...
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0answers
31 views

SYN-ACK with identical MACs

What could cause a CentOS machine to respond with SYN-ACK packet having both source and destination MACs set to the address of the NIC from which the packet is being sent?
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1answer
170 views

Group Policy for Time Sync = ARP Flood?

I have a Windows Server 2008 R2 domain controller and a bunch of workstations of various versions of Windows - XP SP3, Vista, 7, 8.1. Time sync wasn't working correctly on a few PCs so I followed the ...
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2answers
1k views

Ettercap - packet injection / alteration

So I have a proxy setup using squid on port 3128. I also have ettercap setup. My main goal is to change data as it flows through my proxy. Basically, you open up www.something.com using my ...
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0answers
52 views

Strange network issue when moving EC2 elastic IP

Recently we had an issue with a Windows 2012 EC2 server, which meant that we had to move across to another instance. We duplicated the instance, ran some tests and moved over the elastic IP. Should ...
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3answers
510 views

Switch behavior on unicast packets when the destination is unknown

Please let me start by saying I am no network expert, I am a programmer who does a fair amount of L3/4 programming. My question is that when a switch receives a packet with a destination MAC that is ...
0
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2answers
4k views

arp -n responds with (incomplete) on the wrong subnet, can't remove it

context There are 2 servers: server1 - eth0 10.129.76.16 eth0.2 192.168.0.103 server2 - eth0 10.129.79.1 eth0.2 192.168.62.101 The 192.x.x.x addresses are connected to the ...
0
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2answers
136 views

Must an ARP broadcast query packet contain the target node's MAC address [closed]

So far as I know, Address Resolution Protocol (ARP), translates the IP address of a computer on a local network to an equivalent layer 2 address (MAC address), such as sending a packet from machine A ...
2
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1answer
307 views

Determine the hostnames of IP conflict

I have a network with several hundred machines on it. I have a machine that gives intermittent connectivity issues, reported via vSphere web client. This troublesome machine has the hostname ...
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3answers
189 views

Linux (Ubuntu 12.04) sending ARP requests over single interface

I have a system with custom hardware hooked up to 2 different ethernet ports on the same system. The interfaces are configured on the same subnet because the hardware (FPGA-based) has a hardcoded IP ...
0
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0answers
124 views

localhost answering wrong ip

No idea how/why, but here's what I'm seeing. Consider 3 CentOS 5.10 boxes: Host A [10.1.2.7] Host B [10.1.2.8] Host C [10.1.2.9] All of a sudden we're getting strange behavior from Host X, ...
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3answers
73 views

Prevent Linux server host from using ARP

If I know all client will connect to the sever with the same MAC address and to the same interface, is it possible to prevent from server host to send ARP request for each new client IP it gets a ...