# Disables packet forwarding
net.ipv4.ip_forward = 0
# Enables source route verification
net.ipv4.conf.default.rp_filter = 1
# Disables the magic-sysrq key
kernel.sysrq = 0
# Decrease the time default value for tcp_fin_timeout connection
net.ipv4.tcp_fin_timeout = 25
# Decrease the time default value for tcp_keepalive_time connection
net.ipv4.tcp_keepalive_time = 3600
# Turn on the tcp_window_scaling
net.ipv4.tcp_window_scaling = 1
# Turn on the tcp_sack
net.ipv4.tcp_sack = 1
# tcp_fack should be on because of sack
net.ipv4.tcp_fack = 1
# Turn on the tcp_timestamps
net.ipv4.tcp_timestamps = 1
# Enable TCP SYN Cookie Protection
net.ipv4.tcp_syncookies = 1
# Enable ignoring broadcasts request
net.ipv4.icmp_echo_ignore_broadcasts = 1
# Disable ICMP Redirect Acceptance
net.ipv4.conf.all.accept_redirects = 0
# Enable bad error message Protection
net.ipv4.icmp_ignore_bogus_error_responses = 1
# Don't Log Spoofed Packets, Source Routed Packets, Redirect Packets
net.ipv4.conf.all.log_martians = 0
# Make more local ports available
net.ipv4.ip_local_port_range = 1024 65000
# Increase maximum amount of memory allocated to shm
kernel.shmmax = 1073741824
# Improve file system performance
vm.bdflush = 100 1200 128 512 15 5000 500 1884 2
# This will increase the amount of memory available for socket input/output queues
net.ipv4.tcp_rmem = 4096 25165824 25165824
net.core.rmem_max = 25165824
net.core.rmem_default = 25165824
net.ipv4.tcp_wmem = 4096 65536 25165824
net.core.wmem_max = 25165824
net.core.wmem_default = 65536
net.core.optmem_max = 25165824
#ab wann speicher als dreckig betrachtet wird
vm.dirty_ratio=10
vm.dirty_background_ratio=5
#vfs cache pressure
vm.vfs_cache_pressure=50
#gibt den grad an wann ausgelagert wird
vm.swappiness=20
# If you are feeling daring, you can also use these settings below, otherwise just remove them. (Should increase performance)
net.core.netdev_max_backlog = 2500
net.ipv4.tcp_tw_recycle = 1
net.ipv4.tcp_tw_reuse = 1
net.core.rmem_default = 114688
net.core.wmem_default = 114688
net.ipv4.tcp_keepalive_probes = 9
net.ipv4.tcp_retries1 = 3
net.ipv4.tcp_retries2 = 15
net.ipv4.tcp_retrans_collapse = 1
net.ipv4.ip_default_ttl = 64
net.ipv4.ipfrag_time = 30
net.ipv4.ip_no_pmtu_disc = 0
net.unix.max_dgram_qlen = 10
net.token-ring.rif_timeout = 600000
vm.overcommit_memory = 0
vm.page-cluster = 3
kernel.ctrl-alt-del = 0
kernel.panic = 0
kernel.acct = 4 2 30
kernel.printk = 3
kernel.shmall = 2097152
kernel.shmmax = 33554432
dev.raid.speed_limit_min = 1000
dev.raid.speed_limit_max = 200000
After you make the changes to the file, you can make them effective immediately by typing in /sbin/sysctl -p

Also, you will need to issue sysctl -w net.ipv4.route.flush=1 to flush the routing table to make some of these changes happen instantly.

Lastly, you can increase the size of the interface queue by typing /sbin/ifconfig eth0 txqueuelen 1000