Owners Manual

Table Of Contents
13. When a VM moves from one VLT domain to the another VLT domain, the VM host sends the gratuitous GARP. The GARP
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.
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:
Because 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.
LLDP Organizational TLV for Proxy Gateway
Define a new organizational TLV :
LLDP defines an organizationally specific TLV (type 127) with an organizationally unique identifier (0x0001E8) and
organizationally defined subtype (0x01) for sending or receiving this information.
LLDP will uses the existing infrastructure and adds the new TLV, and sends and receives only on the configured ports.
There are only a couple of MAC addresses for each unit to transmit so all currently active MAC addresses are carried on the
newly defined TLV.
This TLV is recognizable only by Dell Networking devices with this feature support. Other devices ignore this field and are
able to process other standard TLVs.
The LLDP organizational TLV passes local destination MAC address information to peer VLT domain devices so they can act as
the proxy gateway. Two configurations are required to enable Proxy Gateway LLDP:
Global proxy gateway LLDP configuration to enable this feature
Interface proxy gateway LLDP configuration to enable/disable proxy-gateway LLDP TLV on particular interfaces
The interface is typically a VLT port-channel which connects to a remote VLT domain
The new proxy gateway TLV is carried on the physical links under the port channel only
There should be at least one link connection to each unit of the VLT domain
Following are the prerequisites for Proxy Gateway LLDP configuration:
LLDP must be globally enabled
VLT Proxy Gateway
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