EIGRP - Stub default behavior
When configuring a stub router in EIGRP, by default, only the connected and summary routes are advertised. For example, if you configure an EIGRP stub router like so:
R1(config)#router eigrp 12 R1(config-router)#eigrp stub
...and then check the running configuration...
R1#show running-config | begin router eigrp router eigrp 12 network 192.168.12.0 no auto-summary eigrp stub connected summary
...you'll notice that the EIGRP stub command, by default, includes the connected and summary routes.
If you explicitly configure any of the possible options for the EIGRP stub feature, only the explicitly configured options are retained. For example, if you configure eigrp stub redistribute, the default values of connected and summary will be removed and only the redistribute option is retained.