• ICMP-based applications like ping and traceroute are exceptions to the preceding logic since we do not have TCP/UDP portnumber. So if source IP address of the packet matches the management port IP address EIS route lookup is done.• Management application packet counter is incremented if EIS route lookup succeeds and packet is sent out of the managementport.• If route lookup in the EIS routing table fails or if the management port is down, then packets are dropped. The managementapplication drop 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 forcomparison with 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 trafficis destined to the front-end port IP address, the response is sent out by doing a route lookup in the default routing table, which isan existing 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 thefront panel port. A and B are end users on the management and front-panel port networks. The OS-initiated traffic for managementapplications takes a preference for ip1 as source IP and uses the management network to reach the destination. If the managementport is down or the route lookup in EIS routing table fails, ip2 is the source IP and the front-panel port is used to reach thedestination. The fallback route between the management and data networks is used in such a case. At any given time, end users canaccess Dell Networking OS applications using either ip1 or ip2. Return traffic for such end-user-originated sessions destined tomanagement port ip1 is handled using the 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 frontpanel port of a switch. End users on the management and front panel port networks are connected. In such an environment, trafficreceived in the management port destined on the data port network is dropped and traffic received in the front-end port destined onthe management network 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 interfaceselection feature is enabled.Table 15. Mapping of Management Applications and Traffic TypeTraffic type /Application type Switch initiated traffic Switch-destined traffic Transit TrafficEIS ManagementApplicationManagement is the preferredegress port selected based onroute lookup in EIS table. If themanagement port is down or theroute lookup fails, packets aredropped.If source TCP/UDP port matches amanagement application and source IPaddress is management port IP address,management port is the preferred egress portselected based on route lookup in EIS table. Ifmanagement port is down or route lookupfails, packets are droppedTraffic frommanagement port todata port and from dataport to managementport is blockedNon-EISmanagementapplicationFront-end default route will takehigher precedence overmanagement default route andSSH session to an unknownIf source TCP/UDP port matches amanagement application and the source IPaddress is a management port IP address, themanagement port is the preferred egress portTraffic frommanagement port todata port and from dataInternet Group Management Protocol (IGMP) 273
