Cisco Cisco IOS Software Release 12.2(2)XA
MGCP 1.0 Including NCS 1.0 and TGCP 1.0 Profiles
max2 lookup
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Cisco IOS Release 12.2(2)XA
max2 lookup
To enable DNS lookup for a new call-agent address after the disconnect threshold timeout value is
reached, use the max2 lookup MGCP profile command. To disable DNS lookup, use the no form of the
command.
reached, use the max2 lookup MGCP profile command. To disable DNS lookup, use the no form of the
command.
max2 lookup
no max2 lookup
Syntax Description
There are no keywords or arguments for this command.
Defaults
Lookup is enabled.
Command Modes
MGCP profile
Command History
Usage Guidelines
Call-agent redundancy can be provided when call agents are identified by DNS name rather than IP
address in the call-agent command, because each DNS name can have more than one IP address
associated with it.
address in the call-agent command, because each DNS name can have more than one IP address
associated with it.
When the active call agent does not respond to a message from the media gateway, the gateway becomes
suspicious that the call agent is out of service. The gateway retransmits the message to the call agent
for the number of times specified in the max1 retries command; this is known as the suspicion
threshold. If there is no response and the max1 lookup command is enabled, the gateway examines the
DNS lookup table to find the IP address of another call agent. If a second call agent is listed, the gateway
retries the message to the second call agent until a response is received or the number of retries specified
in the max1 retries command is reached. This process is repeated for each IP address in the DNS table
until the final address is reached. For the final address, the number of retries is specified by the max2
retries command; this is known as the disconnect threshold. If the number of retries specified in the
max2 retries command is reached and there is still no response and the max2 lookup command is
enabled, the gateway performs one final DNS lookup. If any new IP addresses have been added, the
gateway starts the retransmission process again. Otherwise, the gateway places the endpoint in a
disconnected state.
suspicious that the call agent is out of service. The gateway retransmits the message to the call agent
for the number of times specified in the max1 retries command; this is known as the suspicion
threshold. If there is no response and the max1 lookup command is enabled, the gateway examines the
DNS lookup table to find the IP address of another call agent. If a second call agent is listed, the gateway
retries the message to the second call agent until a response is received or the number of retries specified
in the max1 retries command is reached. This process is repeated for each IP address in the DNS table
until the final address is reached. For the final address, the number of retries is specified by the max2
retries command; this is known as the disconnect threshold. If the number of retries specified in the
max2 retries command is reached and there is still no response and the max2 lookup command is
enabled, the gateway performs one final DNS lookup. If any new IP addresses have been added, the
gateway starts the retransmission process again. Otherwise, the gateway places the endpoint in a
disconnected state.
Examples
The following example shows how to enable the DNS lookup procedure and set the disconnect
retransmission counter value to 9:
retransmission counter value to 9:
Router(config)# mgcp profile nyc-ca
Router(config-mgcp-profile)# call-agent ca1@exp.example.com
Router(config-mgcp-profile)# max2 lookup
Router(config-mgcp-profile)# max2 retries 9
Release
Modification
12.2(2)XA
This command was introduced.