Cisco CCNA / CCNP Certification Test: Troubleshooting Direct Serial Connections
A chief matter of your respective CCNA and CCNP CIT exams might be connecting Cisco routers directly by means of their Serial interfaces, and whilst the configuration is straightforward, there are some vital particulars and demonstrate commands you should know as a way to move the examinations and configure this productively in production and residential lab networks. Let’s Look into a sample configuration.
Connecting Cisco routers straight by way of their Serial interfaces will work very well once you get it operating – and obtaining this type of connection up and managing is not hard enough. You should use clearly show controller serial x to see http://edition.cnn.com/search/?text=인스타 팔로워 구매 which endpoint is performing given that the DCE, and it’s the DCE that needs to be configured Along with the clockrate command.
R3#show controller serial one
High definition device 1, idb = 0x11B4DC, driver construction at 0x121868
buffer sizing 1524 High definition device 1, V.35 DCE cable
R3(config)#int serial1
R3(config-if)#ip deal with 172.twelve.13.3 255.255.255.0
R3(config-if)#clockrate 56000
R3(config-if)#no shut
Failure to configure the clockrate has some interesting results concerning the Actual physical and reasonable point out of your interfaces. Enable’s take away the clockrate from R3 and find out what transpires.
R3(config)#int s1
R3(config-if)#no clockrate 56000
R3(config-if)#
eighteen:02:19: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial1, modified condition to down
The road protocol doesn’t fall quickly, but it does drop. Let’s operate present interface serial1 to match the Actual physical and logical interface states.
R3#show int serial1
Serial1 is up, line protocol is down
Physically, the interface is okay, 인스타그램 팔로워 늘리기 Therefore the Actual physical interface is up. It’s just the reasonable Component of the interface – the line protocol – which is down. It’s the same problem on R1.
R1#present inter serial1
Whilst a router misconfiguration could be the probably reason for a serial relationship difficulty, that’s not the sole cause of clocking concerns. Cisco’s Web site documentation mentions CSU/DSU misconfiguration, out-of-spec cables, poor patch panel connections, and connecting a lot of cables jointly as other motives for clocking problems. Nonetheless, the primary reason behind clocking complications in my encounter is just forgetting to configure the clockrate command!