Forwarding Options
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Use the
no-queue-pairconfiguration to excludequeue-pairfrom the hash calculation (QFX5230-64CD, QFX5240-64OD, and QFX5240-64QD)—Previously, the 5 tuple approach was used for hash calculation to identify a flow. But for remote direct memory access (RDMA) traffic, the 5 tuple hashing mechanism wasn't providing the desired entropy. So consideringqueue-pairinto the hash calculation provided better entropy. Currently,queue-pairis by default included in the hash calculation You can use theno-queue-pairconfiguration to excludequeue-pairfrom the hash calculation.[See enhanced-hash-key.]
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Symmetric hashing support (QFX5130-32CD, QFX5130-48C, QFX5130-48CM, QFX5220, QFX5230-64CD, QFX5240-64OD, QFX5240-64QD, QFX5241-32OD, QFX5241-32QD, QFX5241-64OD, QFX5241-64QD, QFX5241E-64OD, and QFX5700)—Symmetric hashing ensures that bidirectional traffic flows use the same path across ECMP routes or LAGs.
When enabled, symmetric hashing normalizes Layer 3 and Layer 4 fields before computing the hash. This normalization guarantees that forward and reverse traffic produce the same hash value, mapping to the same link or ECMP path. This behavior is important for services that require flow symmetry, such as Network Address Translation (NAT), firewalls, distributed denial-of-service (DDoS) protection, and data collection.
To enable symmetric hashing, use the
set forwarding-options enhanced-hash-key symmetric-hash inet/inet6command.[See enhanced-hash-key.]
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Unknown unicast drop configuration for VLAN interfaces (QFX5130-32CD, QFX5130E-32CD, QFX5130-48C, QFX5130-48CM, QFX5700, and QFX5700E)—You can enhance network performance and prevent traffic storms by configuring your switch to drop unknown unicast packets. This action prevents the flooding of unicast packets with unknown destination MAC addresses across VLAN interfaces.When you enable this feature, the switch learns and adds the source MAC address to the MAC address table. The switch drops packets with unlearned destination MAC addresses. This approach ensures efficient network resource usage and optimal network performance.
[See Understanding and Preventing Unknown Unicast Forwarding.]