inet_peer_minttl

file: /proc/sys/net/ipv4/inet_peer_minttl
variable: net.ipv4.inet_peer_minttl
Official reference

Minimum time-to-live of entries. Should be enough to cover fragment time-to-live on the reassembling side. This minimum time-to-live is guaranteed if the pool size is less than inet_peer_threshold. Measured in seconds.

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