Important Points to Remember
• You can only use one spanned VLAN from a PIM-enabled VLT node to an external neighboring PIM
router.
• If you connect multiple spanned VLANs to a PIM neighbor, or if both spanned and non-spanned
VLANs can access the PIM neighbor, ECMP can cause the PIM protocol running on each VLT peer
node to choose a different VLAN or IP route to reach the PIM neighbor. This can result in issues with
multicast route syncing between peers.
• Both VLT peers require symmetric Layer 2 and Layer 3 configurations on both VLT peers for any
spanned VLAN.
• For optimal performance, configure the VLT VLAN routing metrics to prefer VLT VLAN interfaces over
non-VLT VLAN interfaces.
• When using factory default settings on a new switch deployed as a VLT node, packet loss may occur
due to the requirement that all ports must be open.
• ECMP is not compatible on VLT nodes using VLT multicast. You must use a single VLAN.
Configuring VLT Multicast
To enable and configure VLT multicast, follow these steps.
1.
Enable VLT on a switch, then configure a VLT domain and enter VLT-domain configuration mode.
CONFIGURATION mode
vlt domain
domain-id
2.
Enable peer-routing.
VLT DOMAIN mode
peer-routing
3.
Configure the multicast peer-routing timeout.
VLT DOMAIN mode
multicast peer-routing—timeout
value
value
: Specify a value (in seconds) from 1 to 1200.
4.
Configure a PIM-SM compatible VLT node as a designated router (DR). For more information, refer to
Configuring a Designated Router
.
5.
Configure a PIM-enabled external neighboring router as a rendezvous point (RP). For more
Configuring a Static Rendezvous Point
6.
Configure the VLT VLAN routing metrics to prefer VLT VLAN interfaces over non-VLT VLAN
interfaces. For more information, refer to
7.
Configure symmetrical Layer 2 and Layer 3 configurations on both VLT peers for any spanned VLAN.
Non-VLT ARP Sync
ARP entries (including ND entries) learned on other ports are synced with the VLT peer to support station
move scenarios.
NOTE: ARP entries learned on non-VLT, non-spanned VLANs are not synced with VLT peers.
Virtual Link Trunking (VLT)
1049
Summary of Contents for S4820T
Page 1: ...Dell Configuration Guide for the S4820T System 9 8 0 0 ...
Page 282: ...Dell 282 Control Plane Policing CoPP ...
Page 622: ...Figure 81 Configuring Interfaces for MSDP 622 Multicast Source Discovery Protocol MSDP ...
Page 623: ...Figure 82 Configuring OSPF and BGP for MSDP Multicast Source Discovery Protocol MSDP 623 ...
Page 629: ...Figure 86 MSDP Default Peer Scenario 2 Multicast Source Discovery Protocol MSDP 629 ...
Page 630: ...Figure 87 MSDP Default Peer Scenario 3 630 Multicast Source Discovery Protocol MSDP ...
Page 751: ...10 11 5 2 00 00 05 00 02 04 Member Ports Te 1 2 1 PIM Source Specific Mode PIM SSM 751 ...
Page 905: ...Figure 112 Single and Double Tag First byte TPID Match Service Provider Bridging 905 ...
Page 979: ...6 Member not present 7 Member not present Stacking 979 ...
Page 981: ...storm control Storm Control 981 ...
Page 1103: ...Figure 134 Setup OSPF and Static Routes Virtual Routing and Forwarding VRF 1103 ...