Service Manual
• The above gure shows a sample VLT Proxy gateway scenario. There are no diagonal links in the square VLT connection between
the C and D in VLT domain 1 and C1 and D1 in the VLT domain 2. This causes sub-optimal routing with the VLT Proxy Gateway
LLDP method. For VLT Proxy Gateway to work in this scenario you must congure the VLT-peer-mac transmit command
under VLT Domain Proxy Gateway LLDP mode, in both C and D (VLT domain 1) and C1 and D1 (VLT domain 2). This behavior is
applicable only in the LLDP conguration and not required in the static conguration.
Sample Conguration
Dell(conf-vlt-domain)#proxy-gateway lldp
Dell(conf-vlt-domain-pxy-gw-lldp)#vlt-peer-mac transmit
• Assume the inter-chassis link (ICL) between C1 and D1 is shut and if D1 is the secondary VLT, one half of the inter DC link goes
down. After VM motion, if a packet reaches D2 with the destination MAC address of D1, it may be dropped. This behavior is
applicable only in an LLDP conguration; in a static conguration, the packet is forwarded.
• Any L3 packet, when it gets an L3 hit and is routed, it has a time to live (TTL) decrement as expected.
• You can disable the VLT Proxy Gateway for a particular VLAN using an "Exclude-VLAN" conguration. The conguration has to
be done in both the VLT domains [C and D in VLT domain 1 and C1 and D1 in VLT domain 2].
Sample Conguration LLDP Method
Dell(conf-vlt-domain)#proxy-gateway ll
Dell(conf-vlt-domain-pxy-gw-lldp)#peer-domain-link port-channel 1 exclude-vlan 10
Sample Conguration Static Method
Dell(conf-vlt-domain)#proxy-gateway static
Dell(conf-vlt-domain-pxy-gw-static)#remote-mac-address <xx:xx:xx:xx:xx:xx> exclude-vlan
10
• Packet duplication may happen with “Exclude-VLAN” conguration – Assume you used the exclude-vlan option (called
VLAN 10) in C and D and in C1 and D1; If packets for VLAN 10 with C’s MAC address (C is in VLT domain 1) gets an L3 hit at C1 in
VLT domain 2, they are switched to both D1 (via ICL) and C via inter DC link. This may lead to packet duplication. Therefore, if C’s
MAC address is learned at C1, the packet does not ood to D1 and only switches to C and avoids packet duplication.
• With the existing hardware capabilities, you can only disable VLT Proxy Gateway only for 500 VLANs, using exclude-VLAN
conguration.
Conguring an LLDP VLT Proxy Gateway
You can congure a proxy gateway in a VLT domain to locally route packets destined to a L3 endpoint in another VLT domain.
Apply the following congurations in the Core L3 Routers C and D in the local VLT domain and C1 and D1 in the remote VLT domain:
1. Congure proxy-gateway lldp in VLT Domain Conguration mode.
2. Congure peer-domain-link port-channel <vlt portchannel ID> in VLT Domain Proxy Gateway LLDP mode.
The VLT port channel is the one that connects the remote VLT domain.
Sample Dynamic Proxy Conguration on C switch or C1 switch
Switch_C#conf
Switch_C(conf)#vlt domain 1
Switch_C(conf-vlt-domain1)#proxy-gateway lldp
Switch_C(conf-vlt-domain1-pxy-gw-lldp)#peer-domain-link port-channel 1....
Conguring a Static VLT Proxy Gateway
You can congure a proxy gateway in VLT domains. A proxy gateway allows you to locally route the packets that are destined to an
L3 endpoint of the other VLT domain.
Apply the following congurations in the Core L3 Routers C and D in local VLT domain and C1 and D1 in the remote VLT domain:
1. Congure proxy-gateway static in VLT Domain Conguration mode.
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VLT Proxy Gateway