https://community.cisco.com/t5/network-security/ospf-authentication/m-p/4080897#M1069932 <BR />are those switches connecting with L3 Port channel or SVI ? Wed, 06 May 2020 23:23:16 GMT Martin L 2020-05-06T23:23:16Z https://community.cisco.com/t5/network-security/ospf-authentication/m-p/4080860#M1069929 <P>I am trying to implement OSPF authentication using MD5 between (2) Layer 3 switches. The switches are connected via Port Channel 1 using PagP.&nbsp; When I go into config if&nbsp; Int PO1, there isn't any command syntax related to ip ospf etc etc. I am not sure where or how to enter the message digest key on the interface. Even by configuring or turning on the authentication for the entire area under the router ospf 1 command, i still need to put the key string somewhere.</P><P>&nbsp;</P><P>Using IOS 15.2</P> Wed, 06 May 2020 22:21:32 GMT https://community.cisco.com/t5/network-security/ospf-authentication/m-p/4080860#M1069929 R.D.Mercer 2020-05-06T22:21:32Z https://community.cisco.com/t5/network-security/ospf-authentication/m-p/4080897#M1069932 <BR />are those switches connecting with L3 Port channel or SVI ? Wed, 06 May 2020 23:23:16 GMT https://community.cisco.com/t5/network-security/ospf-authentication/m-p/4080897#M1069932 Martin L 2020-05-06T23:23:16Z