ShirleenPeden17
To earn your Cisco CCNA and CCNP certifications, you've got to master ISDN - and in spite of what some people say, there is nevertheless a lot of ISDN out there that wants to be supported. And when it comes to troubleshooting ISDN, there is a lot to appear at. Is the correct ISDN switchtype configured? Are the dialer map statements correct? What about the dialer-group and dialer-list commands? And that is just the start off.
I usually say that all troubleshooting starts at Layer 1, the Physical layer of the OSI model. The usual approach of troubleshooting ISDN is sending pings across the link, but the connection can be tested with out making use of pings or even prior to assigning IP addresses to the BRI interfaces!
It really is a good thought to location these test calls prior to configuring the interfaces - that way, you know you've got a valid connection ahead of beginning the configuration (and there's a lot of config to go along with ISDN!)
To place a test call with no employing pings, use the isdn contact interface command.
R1#isdn contact interface bri0 8358662
R1#
03:54:43: BR0 DDR: Attempting to dial 8358662
03:54:43: %Hyperlink-3-UPDOWN: Interface BRI0:1, changed state to up
03:54:44: BR0:1 DDR: dialer protocol up
03:54:45: %LINEPROTO-five-UPDOWN: Line protocol on Interface BRI0:1, changed state to up
03:54:49: %ISDN-6-CONNECT: Interface BRI0:1 is now connected to 8358662 R2
To tear the test contact down properly, use isdn disconnect interface. IOS Aid displays the possibilities with this command.
R1#isdn disconnect interface bri ?
all Disconnect the information get in touch with(s) on all b channels
b1 Disconnect the information get in touch with on b1 channel
b2 Disconnect the data get in touch with on b2 channel
R1#isdn disconnect interface bri all
03:58:36: BR0:1 DDR: disconnecting get in touch with
03:58:36: BR0:2 DDR: disconnecting call
03:58:36: %ISDN-six-DISCONNECT: Interface BRI0:1 disconnected from 8358662
R2, get in touch with lasted 20 seconds
03:58:36: %Hyperlink-3-UPDOWN: Interface BRI0:1, changed state to down
03:58:36: BR0:1 DDR: disconnecting contact
03:58:37: %LINEPROTO-5-UPDOWN: Line protocol on Interface BRI0:1, changed state to down
I say "appropriately" simply because the one point you never want to do to end an ISDN call, test or otherwise, is just shut the interface. Telcos do not like it, and ISDN lab devices like it even much less. Usually let the d-channel do its work and tear the contact down in an orderly style - don't just cut it off by shutting the interface down.SDM Software, Inc. 2100 4th St, #132 San Rafael, CA 94901 (415) 670-9302 http://sdmsoftware.com group policy reporting
