Cisco CCNA / CCNP Certification Examination: Troubleshooting Immediate Serial Connections
A first-rate matter of your CCNA and CCNP CIT examinations will be connecting Cisco routers right by means of their Serial interfaces, and while the configuration is easy, there are some crucial particulars and demonstrate instructions you have to know in order to move the tests and configure this properly in output and home lab networks. Allow’s take a look at a sample configuration.
Connecting Cisco routers directly via their Serial interfaces operates rather well when you finally get it functioning – and having such a connection up and working is a snap more than enough. You should utilize exhibit controller serial x to understand which endpoint 인스타 팔로워 is acting given that the DCE, and it’s the DCE that need to be configured Using the clockrate command.
R3#present controller serial one
High definition unit 1, idb = 0x11B4DC, driver structure at 0x121868
buffer dimensions 1524 High definition unit 1, V.35 DCE cable
R3(config)#int serial1
R3(config-if)#ip address 172.12.13.three 255.255.255.0
R3(config-if)#clockrate 56000
R3(config-if)#no shut
Failure to configure the clockrate has some exciting consequences regarding the Actual physical and reasonable state of the interfaces. Enable’s clear away the clockrate from R3 and find out what comes about.
R3(config)#int s1
R3(config-if)#no clockrate 56000
R3(config-if)#
eighteen:02:19: %LINEPROTO-five-UPDOWN: Line protocol on Interface Serial1, transformed condition to down
The line protocol doesn’t fall straight away, however it does drop. Enable’s run display interface serial1 to https://www.washingtonpost.com/newssearch/?query=인스타 팔로워 구매 match the physical and sensible interface states.
R3#clearly show int serial1
Serial1 is up, line protocol is down
Physically, the interface is ok, And so the Actual physical interface is up. It’s just the reasonable Element of the interface – the line protocol – that may be down. It’s the exact same scenario on R1.
R1#show inter serial1
Even though a router misconfiguration is the more than likely explanation for a serial connection concern, that’s not the sole cause of clocking problems. Cisco’s Web site documentation mentions CSU/DSU misconfiguration, out-of-spec cables, terrible patch panel connections, and connecting a lot of cables together as other reasons for clocking problems. Still, the number one cause for clocking difficulties in my expertise is solely forgetting to configure the clockrate command!