Users Guide
How FIP Snooping is Implemented
As soon as the Aggregator is activated in an M1000e chassis as a switch-bridge, existing VLAN-specic and FIP snooping auto-
congurations are applied. The Aggregator snoops FIP packets on VLANs enabled for FIP snooping and allows legitimate sessions. By
default, all FCoE and FIP frames are dropped unless specically permitted by existing FIP snooping-generated ACLs.
FIP Snooping on VLANs
FIP snooping is enabled globally on an Aggregator on all VLANs:
• FIP frames are allowed to pass through the switch on the enabled VLANs and are processed to generate FIP snooping ACLs.
• FCoE trac is allowed on VLANs only after a successful virtual-link initialization (fabric login FLOGI) between an ENode and an FCF. All
other FCoE trac is dropped.
• Atleast one interface is auto-congured for FCF (FIP snooping bridge — FCF) mode on a FIP snooping-enabled VLAN. Multiple FCF
trusted interfaces are auto-congured in a VLAN.
• A maximum of eight VLANs are supported for FIP snooping on an Aggregator. FIP snooping processes FIP packets in trac only from
the rst eight incoming VLANs.
FC-MAP Value
The FC-MAP value that is applied globally by the Aggregator on all FCoE VLANs to authorize FCoE trac is auto-congured.
The FC-MAP value is used to check the FC-MAP value for the MAC address assigned to ENodes in incoming FCoE frames. If the FC-MAP
values does not match, FCoE frames are dropped. A session between an ENode and an FCF is established by the switch —bridge only
when the FC-MAP value on the FCF matches the FC-MAP value on the FIP snooping bridge.
Bridge-to-FCF Links
A port directly connected to an FCF is auto-congured in FCF mode. Initially, all FCoE trac is blocked; only FIP frames are allowed to pass.
FCoE trac is allowed on the port only after a successful FLOGI request/response and conrmed use of the congured FC-MAP value for
the VLAN.
Impact on other Software Features
FIP snooping aects other software features on an Aggregator as follows:
• MAC address learning: MAC address learning is not performed on FIP and FCoE frames, which are denied by ACLs dynamically created
by FIP snooping in server-facing ports in ENode mode.
• MTU auto-conguration: MTU size is set to mini-jumbo (2500 bytes) when a port is in Switchport mode, the FIP snooping feature is
enabled on the switch, and the FIP snooping is enabled on all or individual VLANs.
• Link aggregation group (LAG): FIP snooping is supported on port channels on ports on which PFC mode is on (PFC is operationally up).
FIP Snooping Prerequisites
On an Aggregator, FIP snooping requires the following conditions:
• A FIP snooping bridge requires DCBX and PFC to be enabled on the switch for lossless Ethernet connections (refer to
Data Center
Bridging (DCB)
). Dell recommends that you also enable ETS; ETS is recommended but not required. DCBX and PFC mode are auto-
congured on Aggregator ports and FIP snooping is operational on the port. If the PFC parameters in a DCBX exchange with a peer are
not synchronized, FIP and FCoE frames are dropped on the port.
FIP Snooping
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