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IP ARP: ignored gratuitous arp

alabi_ng
Beginner
Beginner

Hello, 

 

Can anyone help about this persistent log issue that is being broadcast on my switch vlan. I don't know the cause of the consistent broadcast arp and would like to know the solution to it. 

 

Switch model: C3850-48u

Switch version: 03.07.02E

Sw image: cat3k_caa-universalk9

Switch uptime: 3 years, 20 weeks, 2 days, 13 hours, 7 minutes

 

Attached is a screenshot from from my switch log

2 Accepted Solutions

Accepted Solutions

In my experience these are not normal log messages. It looks perhaps like debugging messages. Can you post the output of show debug?

HTH

Rick

View solution in original post

@Richard Burts you are 100% correct. 

 

someone left debugging on for ARP. 

 

I undebugged all and no more arp output again. please find attached. 

 

Thanks everyone for this wonderful support. 

View solution in original post

12 Replies 12

Reza Sharifi
Hall of Fame
Hall of Fame

Hi,

What is vlan 2 used for? Is this a management vlan or a user vlan?

HTH

Hello Reza, 

 

Thanks for looking at this for me.


Vlan 2 is for user vlan and all access ports are connected to it. 

Hi,

Can you describe the problem you are encountering?

 

HTH

All network activities are up and running but my log keep getting flooded with ARP req is dequeued & IP ARP: ignored gratuitous arp. I dont know the cause and am looking for solution. I attached part of screenshot of my log to understand the cause and solution. I have no protection configured on any of the access port. 

 

The excessive log is slowing down any cli command I tried running on the switchport.

I think it normal IP tracking traffic if you config it in SW, 
SW send ARP to host connect to port.

@MHM Cisco World Thank you for your response. IP device tracking wasn't configure on any of the port on this switch. Please find attached and advice why I am getting tons of broadcast gratitious arp, dequeued in my log. Thank you. 

see above comment 

I didn't see it in the uplink switch (Trunk). How can I stop it from filling up the log? Thank you.

In my experience these are not normal log messages. It looks perhaps like debugging messages. Can you post the output of show debug?

HTH

Rick

OK, 
the Client is get IP form DHCP ?
are you config the default GW point to VLAN 2 SVI ?? if not then any client will send ARP ask MAC address for GW.
check this point.

@Richard Burts you are 100% correct. 

 

someone left debugging on for ARP. 

 

I undebugged all and no more arp output again. please find attached. 

 

Thanks everyone for this wonderful support. 

You are welcome. I am glad that my suggestion pointed you in the right direction. Thank you for marking this question as solved. This will help other participants in the community to identify discussions which have helpful information. This community is an excellent place to ask questions and to learn about networking. I hope to see you continue to be active in the community.

HTH

Rick
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