In a deployment where the ProxySG appliance forwards traffic to the Symantec Web Security Service (WSS) and a large number of users use the service, latency increases and page-loading timeouts occur. These issues might occur because the pool of TCP connections is exhausted.
The pool of TCP connections is exhausted because the ProxySG appliance is forwarding traffic to a single destination (WSS) rather than dispersing traffic to multiple public-content providers. Additionally, the pool of connections might also be exhausted by:
This article provides instructions on how to detect and resolve this situation.
To determine if all connections are being consumed, view the statistic for the ProxySG appliance that increases when the appliance was unable to find a source port:
To increase the number of available connections, do the following until the TCP2.214 statistic remains static, and the latency and timeout issues are resolved:
If the issues persist, contact Symantec support for further investigation.
By default, the maximum number of source ports is 16,384. To ensure enough unique connections are available, use the following CLI command to increase the number of ports to the maximum possible for the appliance:
#(config) tcp-ip inet-lowport 1024
For further information, see the KB article: https://support.symantec.com/en_US/article.TECH243235.html
To reduce the amount of time a TCP connection is in the TIME_WAIT state, use the following CLI command:
#(config) tcp-ip tcp-2msl 30
Reducing the TCP TIME_WAIT state value ensures that the ProxySG source ports become reusable more quickly.
To configure additional egress IP addresses from your appliance to WSS:
#(config interface <interface_number>) ip-address <ip-address> <subnet-mask>
Use this option if you want to avoid adding public IP addresses to your ProxySG appliance.
To obtain additional IP addresses for WSS, contact your Symantec point of contact for assistance. When you have the additional IP addresses, do the following:
To set up forwarding hosts:
Create forwarding groups for each WSS port you configured a forward host for. For example, if you created forwarding hosts for ports 8080 and 8443, then you will create two forwarding groups, one for each port.
To create a forwarding group:
To edit the health check for your forwarding group:
Using either the CPL or the VPM, configure policy to reference the appropriate forwarding group names. For information on proxy forwarding policy, see: https://portal.threatpulse.com/docs/sol/connectivity/fixed/proxy/conn-fwdpolicy.htm
Verify that your ProxySG appliance balances traffic equally among the WSS IP addresses.
To verify if load balancing is functioning: