Enabling The Vlt Proxy Gateway - Dell S4820T Configuration Manual

the same subnet, there is no route asymmetry dynamically. But if you configure the static route on
one DC and not on the other, there is asymmetry.
8. If the port-channel specified in theproxy-gateway command is not a VLT LAG, the configuration
is rejected by the CLI. VLT LAG to a legacy LAG when it is part of proxy-gateway.
9. You cannot change the LLDP port channel interface to a legacy LAG when you enable the proxy
gateway.
10. Dell recommends using thevlt-peer-mac transmit command only for square VLTs without
diagonal links.
11. VRRP and IPv6 routing is not supported.
12. Private VLANs (PVLANs) are not supported.
13. When a Virtual Machine (VM) moves from one VLT domain to the another VLT domain, the VM host
send the gratuitous ARP (GARP) , which in-turn triggers a mac movement from the previous VLT
domain to the newer VLT domain.
14. After a station move, if a host sends a TTL1 packet destined to its gateway; for example, a previous
VLT node, the packet may be dropped.
15. After a station move, if a host first PINGs its gateway; for example, a previous VLT node it results a 40
to 60% success rate considering it takes a longer path.
16. L3 frames can be received out-of-order at the L3 cloud when you remove and add back a MAC. This
can happen when proxy gateway routing and sub-optimal routing intersperse witth each other.

Enabling the VLT Proxy Gateway

To enable the VLT Proxy Gateway feature, the system mac addresses of C and D in the local VLT domain
must be installed in C1 and D1 in the remote VLT domain and vice versa. You can install the mac address
in two methods - the proxy-gateway lldp method or the proxy-gateway static configuration.
Proxy-gateway LLDP is a dynamic method of installing the local mac addresses in the remote VLT
domain, which is achieved using a new organizational TLV in LLDP packets.
The VLT proxy gateway can be configured in a VLT domain context using the cli command proxy-
gateway LLDP. You enter the proxy-gateway Configuration mode when you enter this command. The
port-channel interface of the square VLT link on which LLDP packets are to be sent is specified by
thepeer-domain-link port-channel command.
Configuring the proxy gateway lldp and the peer-domain-link port channel, LLDP sets TLV flags
on the interfaces for receiving and transmitting private TLV packets. After defining these organizational
TLV settings, LLDP encodes the local system mac-addresses as organizational TLVs for transmitting to
the peer. If you specify the no proxy gateway LLDP interface command, LLDP stops transmitting
and receiving proxy gateway TLV packets on the specified interfaces. However, other TLVs are not
affected. From the interfaces on which proxy gateway LLDP is enabled, LLDP decodes TLV packets from
the remote LLDP by using the new organizational TLV.
The following requirements must be satisfied for LLDP proxy gateway to function correctly:
• As LLDP is a direct link protocol, data centers must be directly connected.
• LLDP has a limited TLV size. As a result, information that is carried by this new TLV is limited to only
one or two MAC addresses.
• You must ensure proper configuration and physical setup on all related systems.
VLT Proxy Gateway
1041