Cisco CCNA / CCNP Certification Examination: Troubleshooting Immediate Serial Connections
A major subject matter within your CCNA and CCNP CIT tests is going to be connecting Cisco routers immediately via their Serial interfaces, and whilst the configuration is straightforward, there are some very important information and exhibit instructions you must know to be able to pass the tests and configure this efficiently in production and residential lab networks. Permit’s Have a look at a sample configuration.
Connecting Cisco routers right through their Serial interfaces performs really well once you get it operating – and obtaining such a link up and running is simple more than enough. You need to use demonstrate controller serial x to understand which endpoint 인스타그램 팔로워 늘리기 is acting because the DCE, and it’s the DCE that must be configured Along with the clockrate command.
R3#exhibit controller serial one
HD https://en.search.wordpress.com/?src=organic&q=인스타 팔로워 구매 unit 1, idb = 0x11B4DC, driver framework at 0x121868
buffer sizing 1524 High definition device 1, V.35 DCE cable
R3(config)#int serial1
R3(config-if)#ip address 172.12.13.3 255.255.255.0
R3(config-if)#clockrate 56000
R3(config-if)#no shut
Failure to configure the clockrate has some exciting results regarding the physical and rational point out of your interfaces. Enable’s take out the clockrate from R3 and see what takes place.
R3(config)#int s1
R3(config-if)#no clockrate 56000
R3(config-if)#
eighteen:02:19: %LINEPROTO-five-UPDOWN: Line protocol on Interface Serial1, modified condition to down
The line protocol doesn’t drop immediately, but it does fall. Permit’s operate present interface serial1 to compare the Bodily and rational interface states.
R3#display int serial1
Serial1 is up, line protocol is down
Physically, the interface is okay, And so the Bodily interface is up. It’s just the sensible Portion of the interface – the line protocol – that's down. It’s the identical circumstance on R1.
R1#exhibit inter serial1
While a router misconfiguration could be the most likely reason behind a serial connection difficulty, that’s not the sole reason behind clocking concerns. Cisco’s Web site documentation mentions CSU/DSU misconfiguration, out-of-spec cables, negative patch panel connections, and connecting too many cables alongside one another as other causes for clocking issues. However, the primary reason behind clocking difficulties in my knowledge is simply forgetting to configure the clockrate command!