0
votes
0answers
25 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) ...
14
votes
5answers
8k views

ARP broadcast flooding network and high cpu usage

Hoping someone here might have some insight to the issue we are facing. Currently we have Cisco TAC looking at the case but they are struggling to find the root cause. Although the title mentions ARP ...
1
vote
0answers
59 views

Can you SNMP poll the ARP table on Cisco ACE?

I'm trying to get a MAC <=> IP mapping from a Cisco ACE. Unfortunately according to this table, while it supports IP-MIB the ipNetToMediaTable and ipNetToPhysicalTable subtrees are not supported. ...
2
votes
1answer
1k views

Which are the possible reasons for an arp request that is not being solved/answered?

This weekend I was testing a new data link connection from a service provider, and I went through some address resolutions problems. I tested reachability to hosts at the far end using a laptop on my ...
1
vote
1answer
397 views

Broadcom NetXtreme II GigE Teaming Does Not Use Unique MAC, Causing Collisions

I currently have a new Dell server on my local (inside) network that I have setup to use three of the four nics to create a team. Examples below. NIC_1 - mac: 000000000001 - ip: n/a NIC_2 - mac: ...
1
vote
1answer
411 views

Cisco ARP table: determine directly connected devices

I have a Cisco switch and a big list of servers on the network. I need to determine what servers are connected directly to that switch. Will searching for the MAC address of each server in the ...
0
votes
1answer
732 views

One To One NAT, only works on WAN?

We are attempting to test a One To One NAT configuration on a Cisco RV180 router, Cisco SMB support says that this setup below would not work. (they seem to be right) I know it has something to do ...
0
votes
3answers
983 views

ARP broadcast and router performance

My employer subscribes to a fiber based leased Internet from a publicly owned incumbent ISP. The ISP admin says that he cannot give a subnet bigger than /30 because he fears that the ISP edge router ...
0
votes
1answer
323 views

ARP Connectivity on cisco small LAN

I feel so lame to have this doubt, so there is the question : Why do I not have connectivity ? The case is simple, I have configured the topology and have connectivity between each PC and respective ...
0
votes
1answer
105 views

ARP issues across MAN

We have a large area MAN provided by a local cable company. Each location has a cable modem that connects directly back to a central location, i.e. it doesn't cross the internet, it is a private ...
1
vote
1answer
1k 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 ...
1
vote
1answer
1k views

Why is my Nexus 5548UP not adding ARP entries for the trunk to a 2960S?

I have a Nexus 5548UP trunked to a Catalyst 2960S. I have verified that spanning tree is working. I explicitly made the 2960S the root bridge for all VLANs as a temporary measure since it is trunked ...
0
votes
1answer
541 views

CISCO: ARP Poisoning Countermeasures

How can I prevent the Cisco Catalysts 2950/2960/3550/3750 from being vulnerable to ARP Poisoning? Can this be avoided with the ARP INSPECTION? Thanks
1
vote
1answer
318 views

'arp authorized' alternative

Is there another way besides arp authorized command on a cisco router to prevent users from setting static IP addresses on their computers and getting access to the network? Essentially, limiting ...
2
votes
5answers
6k views

Cisco WS-C6509-E Arp Cache Corruption Issue?

We are having an issue with our Catalyst 6500 switch where we suspect that the ARP cache is being corrupted. This presents itself with the following symptoms: When you attempt to ping a system which ...