Help me eBGP, correct me if i'am wrong

General questions
1

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I have a topology like the following, I advertise the network on the dummy interface, I configure eBGP, but why when I check using the command “show ip bgp” the origin code that appears is “i (IGP)” not e (EGP)? I think when using eBGP the origin code that should appear should be e - EGP, is there something wrong? Here is my R1 and R2 configuration.

R1# show protocols bgp
  address-family {
      ipv4-unicast {
          network 192.193.1.0/24 {
          }
          network 192.193.2.0/24 {
          }
          network 192.193.3.0/24 {
          }
      }
  }
  neighbor 192.193.0.2 {
      address-family {
          ipv4-unicast {
          }
      }
      remote-as 65432
      remote-as external
}
  system-as 65431

R2# show protocols bgp
  address-family {
      ipv4-unicast {
          network 192.193.4.0/24 {
          }
          network 192.193.5.0/24 {
          }
          network 192.193.6.0/24 {
          }
      }
  }
  neighbor 192.193.0.1 {
      address-family {
          ipv4-unicast {
          }
      }
      remote-as 65431
      remote-as external
}
  system-as 65432
2

This is correct behavior. You will likely never see EGP origin codes these days.

You are seeing IGP because you’re using the network statement. You would see “?” or incomplete in a redistribution into BGP.

The code, somewhat confusingly, has nothing to do with the neighbor relationship or the if you’re using iBGP vs eBGP.

3

@giga1699 is right , it means that the prefix is learning by IGP ( network connected or added with network) , if you want to be sure , comparing the distance administrative on the bgp outputs, it could helps quickly to identify a EBGP routes over IBGP .

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