RT-AC87R no more 2.4GHz signal!

[γιαννακης]

The 2.4GHz band on my RT-AC87R suddenly stopped working. The thing had been sitting on the same shelf for years; AFAICT, nothing had disturbed it. Is it really possible that the 2.4GHz radio, and only that, just died? It sure appears this way. Let me elaborate:

1. Frequent guest complains that they can't connect to the guest network (which was running on the 2.4GHz band).
2. Apparently only the 5GHz SSID is being advertised; neither the "real" 2.4 SSID nor the guest network SSID can be seen.
3. A visit to the "Guest Network" tab has the first bit of evidence that something is not well: the message "2.4GHz* Turn WiFi on to operate the Guest Network. GO" appears in yellow. OK, maybe somehow it gotten turned off. I follow the GO link, which drops me to the "Professional" tab of the Wireless menu.
4. Unsurprisingly, the radio is already on, and nothing looks out of the ordinary.
5. Power-cycle, clear to factory defaults, power-cycle again: no go.
6. Go to the ASUS site and get the latest available firmware (3.0.0.4.382_52545). Install, reboot, reset to factory defaults, wave a rubber chicken. Still nothing.
7. Look at the system log, still from the gui; nothing jumps out in the general log, but the wireless log only shows the 5GHz band:

   Not associated. Last associated withMode    : AP Only
   
   SSID: "FIVE"
   RSSI: 0 dBm    SNR: 16 dB    noise: -45 dBm    Channel: 153/80
   BSSID: 38:2C:4A:xx:xx:xx    Supported Rates: [ 6(b) 9 12(b) 18 24(b) 36 48 54 ]
   
   Mode    : AP Only

8. Time to get dirty. ssh into the box.
   1. `nvram show`, `nvram show | grep wifi` shows expected interface names (wifi0, eth0, eth1, vlan1, vlan2 ...) but nothing jumps out.
   2. `robocfg show` lists some unexpected (to me) vlans, but I can't tell if they show anything wrong:

 

[γιαννακης]

The 2.4GHz band on my RT-AC87R suddenly stopped working. The thing had been sitting on the same shelf for years; AFAICT, nothing had disturbed it. Is it really possible that the 2.4GHz radio, and only that, just died? It sure appears this way. Let me elaborate:

1. Frequent guest complains that they can't connect to the guest network (which was running on the 2.4GHz band).
2. Apparently only the 5GHz SSID is being advertised; neither the "real" 2.4 SSID nor the guest network SSID can be seen.
3. A visit to the "Guest Network" tab has the first bit of evidence that something is not well: the message "2.4GHz* Turn WiFi on to operate the Guest Network. GO" appears in yellow. OK, maybe somehow it gotten turned off. I follow the GO link, which drops me to the "Professional" tab of the Wireless menu.
4. Unsurprisingly, the radio is already on, and nothing looks out of the ordinary.
5. Power-cycle, clear to factory defaults, power-cycle again: no go.
6. Go to the ASUS site and get the latest available firmware (3.0.0.4.382_52545). Install, reboot, reset to factory defaults, wave a rubber chicken. Still nothing.
7. Look at the system log, still from the gui; nothing jumps out in the general log, but the wireless log only shows the 5GHz band:

   Not associated. Last associated withMode    : AP Only
   
   SSID: "FIVE"
   RSSI: 0 dBm    SNR: 16 dB    noise: -45 dBm    Channel: 153/80
   BSSID: 38:2C:4A:xx:xx:xx    Supported Rates: [ 6(b) 9 12(b) 18 24(b) 36 48 54 ]
   
   Mode    : AP Only

8. Time to get dirty. ssh into the box.
   1. `nvram show`, `nvram show | grep wifi` shows expected interface names (wifi0, eth0, eth1, vlan1, vlan2 ...) but nothing jumps out.
   2. `robocfg show` lists some unexpected (to me) vlans, but I can't tell if they show anything wrong:

(accidentally hit send?)

VLANs: BCM5301x enabled mac_check mac_hash
   1: vlan1: 1 2 3 5 8t
   2: vlan2: 0 8t
1045: vlan1045: 3t 5t 8u
1046: vlan1046: 0t 2t 4 5
1047: vlan1047: 3 7
1099: vlan1099: 1t 2t 5t 8u
1100: vlan1100: 0 3t 5 7t 8t
1101: vlan1101: 5 7t
1102: vlan1102: 0 3 4t 7
1103: vlan1103: 0 1t 2 3t 5 7

THe most confusing part is that the `wl` command cannot find any interface; it always responds with the same message:

admin@RT-AC87R:/tmp/home/root# wl -a eth1  status
wl: wl driver adapter not found

Just for fun, I installed the (unsupported) asus/merlin firmware, no go. Installed several older versions of the asus firmware. No go. I even opened the box looking for burn marks or maybe the remnants of some actual bug ( ), but everything was clean.

Getting a new unit would have been cheaper than spending all this time, except I would instead be wasting time trying to decide *what* to buy.

Except... any ideas what could be wrong?

 

[Tech9]

Is it really possible that the 2.4GHz radio, and only that, just died?

Yes, known to happen to other models as well.

Replace the router, this model is End-of-Life for a long time.