Issue Description
In accounting network of one operator, several Quidway26 routers attach under 36xx router under C enterprise. Its Serial0 is connected with the serial of 36xx router of C enterprise and it acts as master link. AUX connects with 36xx dial-up module of C enterprise through dial-up link and acts as backup of master link. Master link enables OSPF and it is normal. Make related dial-up configuration of AUX of 26 router AND show int AUX0; the physical layer and line protocol are up. Enable OSPF on the interface and Quidway26 cannot learn OSPF route from 36xx of C enterprise.
Handling Process
1. Obtain configuration information of dial-up backup of opposite 36xx and the configuration is as follows:
interface Group-Async1
no ip address
dialer in-band
dialer rotary-group 1
async mode interactive
group-range 97 104
The configuration of opposite router is wrong. The backup interface of Quidway26 is aux 0 and dial-up interface of opposite 36xx router is dialer 1. Dialer 1 bundles to Group-Async1, but async serial of 36xx passes dynamic routing protocol. Async default routing and async dynamic routing must be configured. Add these two commands in Group-Async1 and it is found that OSPF cannot work.
2. Check dial-up configuration of opposite router and it is problematic. The configuration of opposite int dialer1 is as follows:
dialer map ip x.x.x.x. name xxx modem-script dial xxxxxx,
36xx router sends multicast hello packet to external and broadcast (multicast) must be enabled. Add broadcast parameter and OSPF can work.
Root Cause
1. Configure static route on backup link between two routers and Quidway26 router can ping the opposite and other IP addresses. It indicates that physical layer and link layer can pass static route.
2. Confirm dead time and port type of ospf hello packet with opposite router and their cooperation is not problematic.
3. From opposite 36xxdebug ospf information, opposite router can receive hello packet sent by Quidway26, but it does not handle it. It is doubted that the configuration of opposite router is problematic.
Suggestions
Pay attention to dial-up configuration.