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IP Proxy arp doesn't work on CAT5500 RSM TRBRF VLAN I/Fs

Due to legacy IP addressing issues I have 2 DHCP scopes 172.18.1.n and 172.18.2.n. These desktops and of course the DHCP server believe they are on a Class B (/16) network. However, the network is really implementing many 172.18.N.n/24 networks. Previously 2500's and 4700's with secondary addreses to the '.2' network were able to satisfy the '.2' desktops connection request to other 172.18.N.n/24 networks. Through LAN tracing I know this was by IP Proxy ARP functionality. Since attempting to migrate the default router to a CAT5500 RSM with a TRBRF VALN I/F the '.2' desktops are orphaned from other /24 172.18.N networks. Although the proxy arp functionality is enabled ( default ) the arp by thge desktops are not responded to even though the RSM has routes to the requested networks. I have a case opened via my reseller but thought this mighte interest someone here.

  • Other Network Infrastructure Subjects

Re: IP Proxy arp doesn't work on CAT5500 RSM TRBRF VLAN I/Fs

Are you certain proxy arp is enabled? The default recently changed from enable to disabled, I think.