Network statements in Lazy mode & Deep dive into OSPF Network command

During my journey of CCIE, I noticed an OSPF feature worth of sharing. In Core/IGP routing, instead of typing a lot in network commands in OSPF, we can just use network 0.0.0.0 255.255.255.255 and more surprisingly 0.0.0.0 0.0.0.0. Once you enter all zeroes, running-config will convert it to quad 0 followed by quad 255. We can also use 0.0.0.0 0.0.0.0. It just includes all interfaces the same way as if you do 0.0.0.0 255.255.255.255.   Below is the practical demonstration: If the router has all interfaces in a single area, I always use network 0.0.0.0 255.255.255.255 area area-id.    Since, Read More …