AAA and VTY access

Hi All,

I am trying to understand the workings of AAA and here is my question:

When a user telnets into a device that is configured for AAA, the line vty local paswords are ignored, correct?

I have a switch that is configured for AAA and has the following configuration under VTY lines:

line vty 0 4
password 7 3456776457888643
length 0
transport input telnet ssh

I don't seem to understand how would the tacacs authentication work in this scenario. Please note that AAA is configured on this device but no configuration of AAA appears under the VTY lines.

I personally think that the following cofiguration line should appear under the VTY line:

aaa authentication logain default group tacacs+ enable

But, it doesn't, and the user still gets authenticated by tacacs server! Can anyone please explain what might be the cause of this?

Many thanks....
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HodepineConnect With a Mentor Commented:
The aaa commands are in global mode, it's perfectly normal that the config under line contains no login/aaa information.

Have a look at this question, he's got a working aaa setup too:
If tacacs is local (on router) then you have to configure like this:

conf t
aaa new-model
aaa authentication login VTY-LOGIN local
aaa authorization exec VTY-LOGIN local

line vty 0 4
 authorization exec VTY-LOGIN
 login authentication VTY-LOGIN
602650528Connect With a Mentor Commented:
Once aaa-new model and aaa authentication is configured in the global mode on router or switch  using the default name list, it will be used by default by vty access even if nothing is config under line vty.

Tacacs is never local as stated by ampranti, the local in that line means authenticate with password created in router global mode.

Specifying "login authentication VTY-LOGIN" means that you have created an aaa authentication list named VTY-LOGIN under aaa-new model and you want to use that instead of default.
The password 7 3456776457888643 is only used if tacacs server isn't available e.g disconnected from network.

I hope i am a bit clear
Yep. tacacs is never local; I mean "authentication"
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