Hi Guys, I just looked in the F5 log and I saw this error: Aug 24 07:13:29 local/tmm warning tmm[6300]: 01190004:4: address conflict detected for {ip address} (00:1b:21:15:b1:44) on vlan 4091 and there is no such IP address anymore except on the F5 (which own this ip address) Any suggestions? Thanks

If you're using 9.3.x and active-active configuration, SOL8830 might be related: http://support.f5.com/kb/en-us/solutions/public/8000/800/sol8830.html

Hi, 1st of all I want to thank you for your help but I got only 1 machine and the version is 10.x.x Any other idea?or what can I do? Thanks

You said, "there is no such IP address ANYMORE except on the F5." Did that IP address used to exist on another device? If so, it is possible that the F5 still has an ARP entry for that "old" MAC address. Also, is there a firewall on that same VLAN somewhere. If so, the firewall may be Proxy ARP'ing for that address if it is configured for a NAT translation for that address or address space. Joe

Yes, the IP was mistakenly been used by other device, which is not exist anymore, how can I delete the ARP entry of the old MAC address in the F5? The IP is not configured at all in the firewall security and the in the address translation services.

Posted By Ido Katz on 08/24/2010 07:38 AM Yes, the IP was mistakenly been used by other device, which is not exist anymore, how can I delete the ARP entry of the old MAC address in the F5? The IP is not configured at all in the firewall security and the in the address translation services. Through GUI: Network -> Arp -> Dynamic List

IP Conflict?! | DevCentral

19 Replies

hwidjaja_37598
Altostratus
Aug 24, 2010
If you're using 9.3.x and active-active configuration, SOL8830 might be related:

http://support.f5.com/kb/en-us/solutions/public/8000/800/sol8830.html
Ido_Katz_38061
Nimbostratus
Aug 24, 2010
Hi,

1st of all I want to thank you for your help but I got only 1 machine and the version is 10.x.x

Any other idea?or what can I do?

Thanks
Moe_Jartin
Cirrus
Aug 24, 2010
You said, "there is no such IP address ANYMORE except on the F5." Did that IP address used to exist on another device? If so, it is possible that the F5 still has an ARP entry for that "old" MAC address. Also, is there a firewall on that same VLAN somewhere. If so, the firewall may be Proxy ARP'ing for that address if it is configured for a NAT translation for that address or address space.

Joe
Ido_Katz_38061
Nimbostratus
Aug 24, 2010
Yes, the IP was mistakenly been used by other device, which is not exist anymore, how can I delete the ARP entry of the old MAC address in the F5?

The IP is not configured at all in the firewall security and the in the address translation services.
Chris_Miller
Altostratus
Aug 24, 2010
Posted By Ido Katz on 08/24/2010 07:38 AM

Yes, the IP was mistakenly been used by other device, which is not exist anymore, how can I delete the ARP entry of the old MAC address in the F5?

The IP is not configured at all in the firewall security and the in the address translation services.

Through GUI: Network -> Arp -> Dynamic List
Moe_Jartin
Cirrus
Aug 24, 2010
Try "bigpipe arp 10.10.10.20 delete" from the command line. Obviously replacing that IP address with the one in question.
Ido_Katz_38061
Nimbostratus
Aug 24, 2010
How can I be sute that i'm deleting the right arp entry of the old server and not the arp entry of the F5 himself?
Chris_Miller
Altostratus
Aug 24, 2010
Posted By Ido Katz on 08/24/2010 07:55 AM

How can I be sute that i'm deleting the right arp entry of the old server and not the arp entry of the F5 himself?

The F5 shouldn't have a dynamic entry for himself.
Ido_Katz_38061
Nimbostratus
Aug 24, 2010
I couldn't find the address in the dynamic ARP entry for the IP address, any other suggestions?
Chris_Miller
Altostratus
Aug 24, 2010
Posted By Ido Katz on 08/24/2010 08:47 AM

I couldn't find the address in the dynamic ARP entry for the IP address, any other suggestions?

From the command line: arp -a | grep '1.1.1.1' Replace the ip with the one about which you're concerned.'