Refer to the exhibit. While troubleshooting an issue on the network, an engineer notices that a TCP Connect operation failed on port 3000 between R101 and R201. Which command must be configured on R201 to respond to the R101 IP SLA configurations with a control connection on UDP port 1967?
To enable the IP SLA responder on R201 such that it will respond to any IP SLA operations targeted at the device, including the TCP connect operation configured on R101, the correct command is simply 'ip sla responder'. This command enables the IP SLA responder to listen for control messages on the default UDP port 1967, which is used to notify the responder to enable the target port temporarily for the IP SLA operation.
It's D. there are 2 IP SLA configured, one for TCP-Connect and one for Jitter. B would would work but this wants UDP on a specific port. So it is D
It has to be B. The only valid responder commands are: ip sla responder ip sla responder udp-echo ipaddress (ip-address) port (port) vrf (vrf)
I'm sorry that's incorrect, other mentioned commands are also valid. I still think it's B but this explanation instead: "The IP SLA Responder when enabled with the ip sla responder command, does not require the source IP address or the TCP port to be specified. It will listen for control messages on UDP port 1967 and will respond to any IP SLA operations targeted at the device, including TCP Connect to the specified port in the operation."
where the responder listens by default == 1967. so no need to change this default.
It is B
D its the right one to me, additionally in other sites its suggested that UDP setup suggested for the responder is the right one
C is correct. To enable the Cisco IOS IP Service Level Agreements (SLAs) Responder for TCP Connect operations, use the ip sla responder tcp-connect ipaddress command in global configuration mode. see pg 272 in config guide: https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipsla/command/sla-cr-book.pdf
The answer is literally on the question itself.
I think its B. Given they specifically said that control port is used. Implying no need to specify port and ip at destination. I.e the control port will notify the destination what socket to listen on. "IP SLAs use the control protocol to notify the IP SLAs Responder to enable the target port temporarily. This action allows the Responder to reply to the TCP Connect operation." - https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipsla/configuration/xe-16/sla-xe-16-book/sla-tcp-conn.html
Yes, i agree, the port where the responder listens by default == 1967. so no need to change this default.
In my lab environment both B and D works: ip sla 1 tcp-connect 1.1.1.2 30000 source-ip 1.1.1.1 threshold 1 timeout 1 frequency 3 ip sla schedule 1 life forever start-time now
with nothing configured on other side: IOU1#telnet 1.1.1.2 Trying 1.1.1.2 ... Open User Access Verification Username: cisco Password: IOU2>exit IOU1# IOU1#show ip sla statistics IPSLAs Latest Operation Statistics IPSLA operation id: 0 Latest RTT: 0 milliseconds Latest operation start time: 01:29:04 UTC Sun Mar 24 2024 Latest operation return code: Socket connect error Number of successes: 1
when i configure ip sla responder, or ip sla responder udp-echo ipaddress 1.1.1.1 port 1967 everytime I telnet the number of successes goes up by one. ""The IP SLA Responder when enabled with the ip sla responder command, does not require the source IP address or the TCP port to be specified. It will listen for control messages on UDP port 1967 and will respond to any IP SLA operations targeted at the device" hence B seems correct, because we can define a port, but don't have to.
to add to this in my original post the number of successes was 0 when i tried to telnet. with nothing configured on other side: IOU1#telnet 1.1.1.2 Trying 1.1.1.2 ... Open User Access Verification Username: cisco Password: IOU2>exit IOU1# IOU1#show ip sla statistics IPSLAs Latest Operation Statistics IPSLA operation id: 0 Latest RTT: 0 milliseconds Latest operation start time: 01:29:04 UTC Sun Mar 24 2024 Latest operation return code: Socket connect error Number of successes: 0 Then I Turned on ip sla responder, telnet succeeded, then turned it off and telnet failed so number of successes was still at 1. Then i tried option D and it worked and number of successes went up to 2. So B or D works. B is better as it is default listening port.