MikroTik RouterOS v2.9 Reference Manual page 226

In this case the backup interface is an ISDN connection, but in real applications it can be
substituted by a particular connection. Follow the instructions below on how to set up the backup
link:
• At first, you need to set up ISDN connection. To use ISDN, the ISDN card driver must be
loaded:
[admin@MikroTik] driver> add name=hfc
The PPP connection must have a new user added to the routers one and two:
[admin@Mikrotik] ppp secret> add name=backup password=backup service=isdn
An ISDN server and PPP profile must be set up on the second router:
[admin@MikroTik] ppp profile> set default local-address=3.3.3.254
remote-address=3.3.3.1
[admin@MikroTik] interface isdn-server> add name=backup msn=7801032
An ISDN client must be added to the first router:
[admin@MikroTik] interface isdn-client>
add name=backup user="backup" password="backup" phone=7801032 msn=7542159
• Then, you have to set up static routes
Use the /ip route add command to add the required static routes and comments to them.
Comments are required for references in scripts.
The first router:
Page 212 of 695
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