IP ARP: ignored gratuitous arp

[alabi_ng]

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

[Reza Sharifi]

Hi,

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

HTH

[alabi_ng]

Hello Reza, 

Thanks for looking at this for me.

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

[Reza Sharifi]

Hi,

Can you describe the problem you are encountering?

HTH

[alabi_ng]

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.

[MHM Cisco World]

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

[alabi_ng]

@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. 

[MHM Cisco World]

see above comment 

[alabi_ng]

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

[Richard Burts · Accepted solution]

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

[MHM Cisco World]

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.

[alabi_ng · Accepted solution]

@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. 

[Richard Burts]

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.