• If route lookup in the EIS routing table fails or if the management port is down, then packets are dropped. The management applicationdrop counter is incremented.• Whenever IP address is assigned to the management port, it is stored in a global variable in the IP stack, which is used for comparisonwith the source IP address of the packet.• Rest of the response traffic is handled as per existing behavior by doing route lookup in the default routing table. So if the traffic isdestined to the front-end port IP address, the response is sent out by doing a route lookup in the default routing table, which is anexisting behavior.Consider a sample topology in which ip1 is an address assigned to the management port and ip2 is an address assigned to any of the frontpanel port. A and B are end users on the management and front-panel port networks. The OS-initiated traffic for management applicationstakes a preference for ip1 as source IP and uses the management network to reach the destination. If the management port is down or theroute lookup in EIS routing table fails, ip2 is the source IP and the front-panel port is used to reach the destination. The fallback routebetween the management and data networks is used in such a case. At any given time, end users can access Dell Networking OSapplications using either ip1 or ip2. Return traffic for such end-user-originated sessions destined to management port ip1 is handled usingthe EIS route lookup.Handling of Transit Traffic (Traffic Separation)This is forwarded traffic where destination IP is not an IP address configured in the switch.• Packets received on the management port with destination on the front-end port is dropped.• Packets received on the front-end port with destination on the management port is dropped.• A separate drop counter is incremented for this case. This counter is viewed using the netstat command, like all other IP layercounters.Consider a scenario in which ip1 is an address assigned to the management port and ip2 is an address assigned to any of the front panelport of a switch. End users on the management and front panel port networks are connected. In such an environment, traffic received inthe management port destined on the data port network is dropped and traffic received in the front-end port destined on the managementnetwork is dropped.Mapping of Management Applications and Traffic TypeThe following table summarizes the behavior of applications for various types of traffic when the management egress interface selectionfeature is enabled.Table 36. Mapping of Management Applications and Traffic TypeTraffic type /Application type Switch initiated traffic Switch-destined traffic Transit TrafficEIS ManagementApplicationManagement is the preferred egressport selected based on route lookupin EIS table. If the management portis down or the route lookup fails,packets are dropped.If source TCP/UDP port matches a managementapplication and source IP address is managementport IP address, management port is thepreferred egress port selected based on routelookup in EIS table. If management port is downor route lookup fails, packets are droppedTraffic from managementport to data port andfrom data port tomanagement port isblockedNon-EISmanagementapplicationFront-end default route will takehigher precedence overmanagement default route and SSHsession to an unknown destinationuses the front-end default routeIf source TCP/UDP port matches a managementapplication and the source IP address is amanagement port IP address, the managementport is the preferred egress port selected basedon route lookup in EIS table. If the managementTraffic from managementport to data port andfrom data port tomanagement port isblockedInternet Group Management Protocol (IGMP) 387
