confused on tty and async

[rbelt]

looking @ a 2520 (1 eth, 2 ser, 2 ser/async, 1 bri).

'sho line' reports the cons, aux and vty's (cons @ 0, aux @ 4 so absolute numbers 1-3 are unaccounted for)

'sho users all' reports the cons, aux, and vty's but also adds 3 tty's (absolute numbers 1-3)

Using 'int async' I'm only given the option to configure async 4 (the aux). I figured that I would be able to configure the 2 ser/async lines using 'int async' (I can configure these via 'int serial' and they work fine in that role). My assumption is that I could put modems on these interfaces (hence the need to use 'int async'). I do notice that the 2 ser/async interfaces are in 'sync' mode...

So the questions are:

what are the 3 TTY's (specifically, why 3) and why can't I configure the 2 ser/async lines using 'int async'

thanks

//RB

 

[ewiley]

Do a "show interface" to see what interfaces you have. I don't have any direct experience with the slow-speed async interfaces on the 2520, but I suspect they might show up as "serial x" interfaces. I'm not sure if you'll need the "physical-layer async" interface command in that case, since it'd probably be implied by the hardware configuration.

 

[ewiley]

Oops, I guess I should have read your whole post first.. Yes, you can attach modems to them, you just have to put the "physical-layer async" in the interface config of serial x and you should be good to go.

 

[rbelt]

great! I shifted the serial interfaces to async and now TTY 2 and 3 show up in 'sho line' still some issues though:

TTY 1 is still 'missing' with:
"Line(s) not in async mode -or- with no hardware support" = 1
Is the TTY1 reserved for BRI and isn't present because it's offline (not connected) -- that would make sense to me.

Also, I'm unable to configure anything other than 'int async 4' (which is the aux) -- 2 and 3 are not options...

thanks

//RB