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You have a couple of options. <br />
<br />
You could try <b>show ip arp inspection log</b><br />
<br />
If you have DHCP snooping enabled, you could also use <b>show ip DHCP snooping binding</b>
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sh ip arp ... does not show any good info. I do not have dhcp snooping enabled
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Try pinging your networks broadcast address from the switch and check arp table again, you should have more or less full table.
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Or you could try SPAN port to capture all the traffics from that trunk
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What you are asking for is not actually the job of a L2/L3 switch. The IP/MAC/Port details are transient and will appear in and time out of the switch's cache as necessary (this is just how Ethernet works and how it dynamically converges in the event of topology changes). All you can do is use different tools to gather the info you need.<br />
<br />
Not sure how big your network is, can you not ask the person running the VMWare instance how many servers\desktops are behind that port?
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I sure can ask the person for the number of hosts behind a port. I can also use SPAN and Wiresharl. But it will be great if there is a command that can list all the MAC address behind a port. Now that I think about it, how about the sh CAM table. I will try it tomorrow.
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There's no way to get information on a MAC address that hasn't been active on the network, so by generating traffic and following it up with the &quot;show mac&quot; command, you'll have better results.<br />
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Using tclsh and doing a ping sweep of the subnets with a zero timeout will quickly generate ARP responses to populate the switch's database and give you useful information.<br />
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tclsh<br />
for { set i 1} { i &lt;&nbsp;255 } { incr i } { ping x.x.x.$i repeat 1 timeout 0 }<br />
exit
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Do you use that switch as a layer 2 or layer 3 device?<br />
If layer 3, it might have ARP info.<br />
If layer 2, you'll need at least DHCP snooping to get any kind of MAC-to-IP database built on it, as I understand.
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Jody,<br />
<br />
show mac address-table interface x<br />
<br />
That is the command that I was looking for. When I did that command, I see about 30 devices behind my port. Thanks
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<div class="content wysiwyg-content">
I have a Cisco Catalyst 3750 and I'd like to find out all the IP addresses (devices) connecting to a port. the sh mac add add &lt;MAC_ADDR&gt; only shows the port of a known MAC address. In my case, I know that the port is a trunk, I'd like to find out how many IP addresses are behind that one port. I believe there is a VMWare host connecting to that port. Thx
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I have a Cisco Catalyst 3750 and I'd like to find out all the IP addresses (devices) connecting to a port. the sh mac add add <MAC_ADDR> only shows the port of a known MAC address. In my case, I know that the port is a trunk, I'd like to find out how many IP addresses are behind that one port. I believe there is a VMWare host connecting to that port. Thx

devices attached to a Cisco port

A switch is a device that filters and forwards packets of data between LAN segments. Switches operate at the data link layer or the network layer of the Open Systems Interconnection (OSI) Reference Model and therefore support any packet protocol. LANs that use switches to join segments are called switched LANs or, in the case of Ethernet networks, switched Ethernet LANs. A hub is a connection point for devices in a network. Hubs are commonly used to connect segments of a LAN. A hub contains multiple ports; when a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets.

Switches / Hubs

Networking is the process of connecting computing devices, peripherals and terminals together through a system that uses wiring, cabling or radio waves that enable their users to communicate, share information and interact over distances. Often associated are issues regarding operating systems, hardware and equipment, cloud and virtual networking, protocols, architecture, storage and management.

Networking

Network analysis is the process of identifying and remediating the processes and systems within a network, including performance, connectivity and security. The process is performed through the use of tools developed for monitoring and analyzing network activity. Network problems that involve finding an optimal way of doing something are studied under the name combinatorial optimization. Examples include network flow, shortest path problem, transport problem, transshipment problem, location problem, matching problem, assignment problem, packing problem, routing problem, Critical Path Analysis and PERT (Program Evaluation & Review Technique).