CCNA Test good results is dependent mainly on noticing the details, and this is especially true of configurations involving right linked serial interfaces. Not to mention, it’s not adequate to note these facts – you’ve received to learn how to proceed about them!
A Cisco router is often a DTE by default, but instantly connecting two DTEs using a DCE/DTE cable is not sufficient. In the next illustration, R1 and R3 are instantly related at their Serial1 interfaces. The line goes up briefly just after currently being opened, but the road protocol goes down following about 30 seconds.
R3(config-if)#int s1
R3(config-if)#ip handle 172.12.thirteen.three 255.255.255.0
R3(config-if)#no shutdown
2d18h: %Backlink-3-UPDOWN: Interface Serial1, transformed point out to up
2d18h: %LINEPROTO-five-UPDOWN: Line protocol on Interface Serial1, modified state to up
R3(config-if)#
2d18h: %LINEPROTO-five-UPDOWN: Line protocol on Interface Serial1, modified state to down
The trouble is among the routers needs to act since the DCE to ensure that the road protocol to return up and not sleep. If this have been your CCNA / CCNP house lab, you could possibly just go above and look at the DTE/DCE cable to see which router had the DCE conclude of your cable attached. In this instance, however, we don’t have Actual physical access to the routers. How can we explain to which router has the DCE conclusion on the cable attached?
R3#clearly show controller serial one
High definition unit one, idb = 0x1C44E8, driver construction at 0x1CBAC8
buffer dimensions 1524 HD device one, V.35 DCE cable
The present controller command provides us this data. (There’s a good deal extra output this with this command, nonetheless it’s unimportant for our purposes.) The router While using the DCE conclude with the cable needs to produce a clock price for the DTE, and we’ll just do that Together with the interface-stage clockrate command.
R3#conf t
Enter configuration commands, just one for each line. Conclusion with CNTL/Z.
R3(config)#int serial1
R3(config-if)#clockrate 56000
In just a couple seconds, the road protocol goes up and stays up.
When troubleshooting a relationship, normally run present 먹튀검증업체 interface very first. If the thing is The mix proven underneath, the connection is bodily fantastic but logically down. That’s generally the results of a required keepalive not remaining existing. With Body Relay, it’s in all probability an LMI situation, but with directly related serial interfaces The difficulty is most probably the DCE stop on the connection not giving clockrate.
R3#display interface serial one
Serial1 is up, line protocol is down
Troubleshooting is a major Portion of the job, and it’s a major part of the Cisco CCNA and CCNP packages http://query.nytimes.com/search/sitesearch/?action=click&contentCollection®ion=TopBar&WT.nav=searchWidget&module=SearchSubmit&pgtype=Homepage#/먹튀검증 likewise. Know your display and debug instructions and also you’re on the approach to passing the CCNA!