Les machines sont puissantes, le réseau est rapide, et pourtant à partir d'un certain nombre de connexions TCP des erreurs apparaissent, comme too many open files.

Sources:

• https://klaver.it/linux/sysctl.conf

$ cat /etc/sysctl.d/local.conf
 
# Increase number of incoming connections
net.core.somaxconn = 1024
# Increase number of incoming connections backlog
net.core.netdev_max_backlog = 4096
 
# Decrease the time default value for tcp_fin_timeout connection
net.ipv4.tcp_fin_timeout = 15
# Decrease the time default value for connections to keep alive
net.ipv4.tcp_keepalive_time = 300
net.ipv4.tcp_keepalive_probes = 5
net.ipv4.tcp_keepalive_intvl = 15
 
# try to reuse time-wait connections, but don't recycle them (recycle can break clients behind NAT)
net.ipv4.tcp_tw_recycle = 0
net.ipv4.tcp_tw_reuse = 1

À avoir :

• tcp_keepalive_time
• /proc/sys/net/ipv4/tcp_tw_recycle
• /proc/sys/net/ipv4/tcp_tw_reuse