Determines whether TCP performs dead gateway detection. Dead gateway detection is a TCP feature that identifies gateways that are not operating properly and that switches the computer to a new default gateway.

When enabled, any given connection defines a gateway as non-operational ( dead ) when a packet sent to the gateway must be retransmitted more than half of the number of times specified in the value of the TcpMaxDataRetransmissions entry. The connection switches to the next gateway in the list in the DefaultGateway or DhcpDefaultGateway entries. The system defines a gateway as dead when more than 25 percent of its connections have switched to the next default gateway in the list.

To define backup gateways, use Network and Dial-up Connections. Right-click Local Area Connection, click Properties, click Internet Protocol (TCP/IP), and then click the Properties button. On the General tab, click the Advanced button, click the IP Settings tab, and then, in the Default gateways, in order of use section, click Add.

When the application is not used for a significant amount of time, the firewall setting between database & application server closes physical connection between application & database. This will invalidate the connection in connection pool. To detect such dead connections … Continue reading →

Determines whether TCP performs dead gateway detection. Dead gateway detection is a TCP feature that identifies gateways that are not operating properly and that switches the computer to a new default gateway.

When enabled, any given connection defines a gateway as non-operational ( dead ) when a packet sent to the gateway must be retransmitted more than half of the number of times specified in the value of the TcpMaxDataRetransmissions entry. The connection switches to the next gateway in the list in the DefaultGateway or DhcpDefaultGateway entries. The system defines a gateway as dead when more than 25 percent of its connections have switched to the next default gateway in the list.

To define backup gateways, use Network and Dial-up Connections. Right-click Local Area Connection, click Properties, click Internet Protocol (TCP/IP), and then click the Properties button. On the General tab, click the Advanced button, click the IP Settings tab, and then, in the Default gateways, in order of use section, click Add.

When the application is not used for a significant amount of time, the firewall setting between database & application server closes physical connection between application & database. This will invalidate the connection in connection pool. To detect such dead connections … Continue reading →

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Since our oracle 10g RAC has been moved behind firewall, we always get disconnected/timeout by firewall if the connection was idle.
By searching the metalink i found this article is really useful:

Firewall(FW) has become common in today’s networking to protect the network environment. The firewall recognizes the TCP protocol and it records the client server socket end-points. Also, FW recognize the TCP connection closure, and then will release the resources allocated for recording the opening connection. For every end-point pairs , the firewall must also allocate some resources(may be small).

Initially FW were designed to protect the application servers, network and then to protect client/server connection. With these in mind, a time-out in terms of hours (1 hour is the default for most FW) is reasonable. With the advent of more complex security schemes, FW are not only between client and server, but also between different application servers ( intranet, demilitarized zone (DMZ) , and such) and database servers. So, the horizon of 1 hour idle time for communication between servers maybe not be appropriate.

Determines whether TCP performs dead gateway detection. Dead gateway detection is a TCP feature that identifies gateways that are not operating properly and that switches the computer to a new default gateway.

When enabled, any given connection defines a gateway as non-operational ( dead ) when a packet sent to the gateway must be retransmitted more than half of the number of times specified in the value of the TcpMaxDataRetransmissions entry. The connection switches to the next gateway in the list in the DefaultGateway or DhcpDefaultGateway entries. The system defines a gateway as dead when more than 25 percent of its connections have switched to the next default gateway in the list.

To define backup gateways, use Network and Dial-up Connections. Right-click Local Area Connection, click Properties, click Internet Protocol (TCP/IP), and then click the Properties button. On the General tab, click the Advanced button, click the IP Settings tab, and then, in the Default gateways, in order of use section, click Add.

When the application is not used for a significant amount of time, the firewall setting between database & application server closes physical connection between application & database. This will invalidate the connection in connection pool. To detect such dead connections … Continue reading →

My Oracle Support provides customers with access to over a
Million Knowledge Articles and hundreds of Community platforms

Determines whether TCP performs dead gateway detection. Dead gateway detection is a TCP feature that identifies gateways that are not operating properly and that switches the computer to a new default gateway.

When enabled, any given connection defines a gateway as non-operational ( dead ) when a packet sent to the gateway must be retransmitted more than half of the number of times specified in the value of the TcpMaxDataRetransmissions entry. The connection switches to the next gateway in the list in the DefaultGateway or DhcpDefaultGateway entries. The system defines a gateway as dead when more than 25 percent of its connections have switched to the next default gateway in the list.

To define backup gateways, use Network and Dial-up Connections. Right-click Local Area Connection, click Properties, click Internet Protocol (TCP/IP), and then click the Properties button. On the General tab, click the Advanced button, click the IP Settings tab, and then, in the Default gateways, in order of use section, click Add.

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