Monthly Archives: June, 2013

OTV and MTU

OTV Header Format Some consideration must be given to the MTU across the transport infrastructure. Consider the OTV packet header layout. A 42 byte OTV header is added and the DF (Don’t Fragment) bit is set on ALL OTV packets. The DF bit is set because the Nexus 7000 does not support fragmentation and reassembly. …

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vPC Role

There are two defined vPC roles: primary and secondary.vPC role defines which of the two vPC peer devices processes Bridge Protocol Data Units (BPDUs) and responds to Address Resolution Protocol (ARP).Use role priority <value> command (under vPC domain configuration context) to force vPC role to primary for a dedicated peer device.<value> ranges from 1 to …

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iSCSI Qos N5K

Identify iSCSI traffic : class-map type qos class-iscsimatch protocol iscsimatch cos 4class-map type queuing class-iscsimatch qos-group 4policy-map type qos iscsi-in-policyclass type qos class-fcoeset qos-group 1class type qos class-iscsiset qos-group 4 policy-map type queuing iscsi-in-policyclass type queuing class-iscsibandwidth percent 10class type queuing class-fcoebandwidth percent 10class type queuing class-defaultbandwidth percent 80policy-map type queuing iscsi-out-policyclass type queuing class-iscsibandwidth …

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iSCSI Ports

iSCSI uses TCP (typically TCP ports 860 and 3260).