---
title: Tuning network and TCP settings
description: Increase the performance and capacity of the networking, particularly TCP, stack to enable PingAccess to handle a high volume of concurrent requests.
component: pingaccess
version: 9.0
page_id: pingaccess:reference_guides:pa_tuning_network_and_tcp_settings
canonical_url: https://docs.pingidentity.com/pingaccess/9.0/reference_guides/pa_tuning_network_and_tcp_settings.html
revdate: January 12, 2024
section_ids:
  steps: Steps
---

# Tuning network and TCP settings

Increase the performance and capacity of the networking, particularly TCP, stack to enable PingAccess to handle a high volume of concurrent requests.

## Steps

1. Edit the `/etc/sysctl.conf` file.

2. Add or modify the following properties:

   ```
   ##TCP Tuning##
   # Controls the use of TCP syncookies (default is 1)
   # and increase the number of outstanding syn requests allowed.
   net.ipv4.tcp_syncookies=1
   net.ipv4.tcp_max_syn_backlog=8192

   # Increase number of incoming connections.
   # somaxconn defines the number of request_sock structures allocated
   # per each listen call.
   # The queue is persistent through the life of the listen socket.
   net.core.somaxconn=4096

   # Increase number of incoming connections backlog queue.
   # Sets the maximum number of packets, queued on the INPUT side,
   # when the interface receives packets faster
   # than kernel can process them.
   net.core.netdev_max_backlog=65536

   # increase system IP port limits
   net.ipv4.ip_local_port_range=2048 65535

   # Turn on window scaling which can enlarge the transfer window:
   net.ipv4.tcp_window_scaling=1

   # decrease TCP timeout
   net.ipv4.tcp_fin_timeout=10

   # Allow reuse of sockets in TIME_WAIT state for new connections
   # (While this may increase performance, use with caution according
   # to the kernel documentation.  This setting should only be enabled
   # after the system administrator reviews security considerations.)
   net.ipv4.tcp_tw_reuse=1

   # Increase the read and write buffer space allocatable
   # (minimum size, initial size, and maximum size in bytes)
   net.ipv4.tcp_rmem = 4096 65536 16777216
   net.ipv4.tcp_wmem = 4096 65536 16777216

   # The maximum number of packets which may be queued
   # for each unresolved address by other network layers
   net.ipv4.neigh.default.unres_qlen=100
   net.ipv4.neigh.eth0.unres_qlen=100
   net.ipv4.neigh.em1.unres_qlen=100

   # Default Socket Receive and Write Buffer
   net.core.rmem_default=8388608
   net.core.wmem_default=8388608
   ##############
   ```