Limit on the number of Wifi ssids?

I am trying to create a number of different WiFI ssids on a tl-wr841n-v13 running 19.07. 4 seems to work, but 5 seems to fail. Four is probably enough for me, but I am curious about the origin of the limit.

Is this an OpenWRT limit, or something specific to the mt76 chipset?

Running iw list will tell you the valid interface combinations.

On most devices the number of concurrent AP interfaces is usually in the 4-8 (maybe 16, for very new/ highend ones) range, this is a hardware (firmware) limitation.


Adding an example to slh's post, r7800 (what i'd call newer):

valid interface combinations:
    * #{ managed } <= 16, #{ AP, mesh point } <= 16, #{ IBSS } <= 1,
     total <= 16, #channels <= 1, STA/AP BI must match, radar detect widths: { 20 MHz (no HT), 20 MHz, 40 MHz, 80 MHz, 80+80 MHz, 160 MHz }

16 is the upper limit for APs


On a 841 v13 I see:

   max # scan SSIDs: 4

   valid interface combinations:
             * #{ IBSS } <= 1, #{ managed, AP, mesh point } <= 4,
               total <= 4, #channels <= 1, STA/AP BI must match

I assume the scan SSIDs is something different. (On the c7 this number does NOT match the number in the "valid interface combinations")

Thank you both!

It would be nice if the gui warned you when you try to create too many ssids, but I guess it is rare that people do this.