I'm using OpenWrt 19.07.2 r10947-65030d81f3 on FritzBox 4040.
The wireless interfaces take a lot of time to be initialized after reboot and often they appear to be up (as seen in Wireless Overview in Luci) but interfaces listed are shown with " Error: Network device is not present".
dmesg shows (not sure if error -2 is anything to worry about):
root@fritz:~# dmesg | grep -E '(ath|wlan)'
[ 129.957270] ath10k_ahb a000000.wifi: Direct firmware load for ath10k/fwcfg-ahb-a000000.wifi.txt failed with error -2
[ 129.957361] ath10k_ahb a000000.wifi: Falling back to user helper
[ 130.032651] firmware ath10k!fwcfg-ahb-a000000.wifi.txt: firmware_loading_store: map pages failed
[ 130.032965] ath10k_ahb a000000.wifi: Direct firmware load for ath10k/pre-cal-ahb-a000000.wifi.bin failed with error -2
[ 130.040611] ath10k_ahb a000000.wifi: Falling back to user helper
[ 130.492652] ath10k_ahb a000000.wifi: Direct firmware load for ath10k/QCA4019/hw1.0/ct-firmware-5.bin failed with error -2
[ 130.492701] ath10k_ahb a000000.wifi: Falling back to user helper
[ 130.555073] firmware ath10k!QCA4019!hw1.0!ct-firmware-5.bin: firmware_loading_store: map pages failed
[ 130.555399] ath10k_ahb a000000.wifi: Direct firmware load for ath10k/QCA4019/hw1.0/ct-firmware-2.bin failed with error -2
[ 130.563309] ath10k_ahb a000000.wifi: Falling back to user helper
[ 130.641199] firmware ath10k!QCA4019!hw1.0!ct-firmware-2.bin: firmware_loading_store: map pages failed
[ 130.641620] ath10k_ahb a000000.wifi: Direct firmware load for ath10k/QCA4019/hw1.0/firmware-6.bin failed with error -2
[ 130.649538] ath10k_ahb a000000.wifi: Falling back to user helper
[ 130.732597] firmware ath10k!QCA4019!hw1.0!firmware-6.bin: firmware_loading_store: map pages failed
[ 131.253313] ath10k_ahb a000000.wifi: qca4019 hw1.0 target 0x01000000 chip_id 0x003b00ff sub 0000:0000
[ 131.253360] ath10k_ahb a000000.wifi: kconfig debug 0 debugfs 1 tracing 0 dfs 1 testmode 0
[ 131.265012] ath10k_ahb a000000.wifi: firmware ver 10.4b-ct-4019-fW-012-17ba98334 api 5 features mfp,peer-flow-ctrl,txstatus-noack,wmi-10.x-CT,ratemask-CT,regdump-CT,txrate-CT,flush-all-CT,pingpong-CT,
ch-regs-CT,nop-CT,set-special-CT,tx-rc-CT,cust-stats-CT,txrate2-CT,beacon-cb-CT,wmi-block-ack-CT,wmi-bcn-rc-CT crc32 8f2e0e09
[ 131.356472] ath10k_ahb a000000.wifi: board_file api 2 bmi_id 0:16 crc32 e2dfaa91
[ 132.665430] ath10k_ahb a000000.wifi: 10.4 wmi init: vdevs: 16 peers: 48 tid: 96
[ 132.665478] ath10k_ahb a000000.wifi: msdu-desc: 2500 skid: 32
[ 132.700644] ath10k_ahb a000000.wifi: wmi print 'P 48/48 V 16 K 144 PH 176 T 186 msdu-desc: 2500 sw-crypt: 0 ct-sta: 0'
[ 132.703702] ath10k_ahb a000000.wifi: wmi print 'free: 56528 iram: 23400 sram: 32520'
[ 132.836301] ath10k_ahb a000000.wifi: htt-ver 2.2 wmi-op 6 htt-op 4 cal pre-cal-file max-sta 32 raw 0 hwcrypto 1
[ 132.970398] ath: EEPROM regdomain: 0x0
[ 132.970411] ath: EEPROM indicates default country code should be used
[ 132.970416] ath: doing EEPROM country->regdmn map search
[ 132.970426] ath: country maps to regdmn code: 0x3a
[ 132.970434] ath: Country alpha2 being used: US
[ 132.970439] ath: Regpair used: 0x3a
[ 133.156082] ath10k_ahb a800000.wifi: Direct firmware load for ath10k/fwcfg-ahb-a800000.wifi.txt failed with error -2
[ 133.156137] ath10k_ahb a800000.wifi: Falling back to user helper
[ 133.528440] firmware ath10k!fwcfg-ahb-a800000.wifi.txt: firmware_loading_store: map pages failed
[ 133.528793] ath10k_ahb a800000.wifi: Direct firmware load for ath10k/pre-cal-ahb-a800000.wifi.bin failed with error -2
[ 133.536368] ath10k_ahb a800000.wifi: Falling back to user helper
[ 133.735297] ath10k_ahb a800000.wifi: Direct firmware load for ath10k/QCA4019/hw1.0/ct-firmware-5.bin failed with error -2
[ 133.735352] ath10k_ahb a800000.wifi: Falling back to user helper
[ 133.811817] firmware ath10k!QCA4019!hw1.0!ct-firmware-5.bin: firmware_loading_store: map pages failed
[ 133.812184] ath10k_ahb a800000.wifi: Direct firmware load for ath10k/QCA4019/hw1.0/ct-firmware-2.bin failed with error -2
[ 133.820124] ath10k_ahb a800000.wifi: Falling back to user helper
[ 133.891986] firmware ath10k!QCA4019!hw1.0!ct-firmware-2.bin: firmware_loading_store: map pages failed
[ 133.892349] ath10k_ahb a800000.wifi: Direct firmware load for ath10k/QCA4019/hw1.0/firmware-6.bin failed with error -2
[ 133.900293] ath10k_ahb a800000.wifi: Falling back to user helper
[ 133.961109] firmware ath10k!QCA4019!hw1.0!firmware-6.bin: firmware_loading_store: map pages failed
[ 133.961437] ath10k_ahb a800000.wifi: qca4019 hw1.0 target 0x01000000 chip_id 0x003b00ff sub 0000:0000
[ 133.969090] ath10k_ahb a800000.wifi: kconfig debug 0 debugfs 1 tracing 0 dfs 1 testmode 0
[ 133.983414] ath10k_ahb a800000.wifi: firmware ver 10.4b-ct-4019-fW-012-17ba98334 api 5 features mfp,peer-flow-ctrl,txstatus-noack,wmi-10.x-CT,ratemask-CT,regdump-CT,txrate-CT,flush-all-CT,pingpong-CT,
ch-regs-CT,nop-CT,set-special-CT,tx-rc-CT,cust-stats-CT,txrate2-CT,beacon-cb-CT,wmi-block-ack-CT,wmi-bcn-rc-CT crc32 8f2e0e09
[ 134.037513] ath10k_ahb a800000.wifi: board_file api 2 bmi_id 0:17 crc32 e2dfaa91
[ 135.346472] ath10k_ahb a800000.wifi: 10.4 wmi init: vdevs: 16 peers: 48 tid: 96
[ 135.346524] ath10k_ahb a800000.wifi: msdu-desc: 2500 skid: 32
[ 135.383836] ath10k_ahb a800000.wifi: wmi print 'P 48/48 V 16 K 144 PH 176 T 186 msdu-desc: 2500 sw-crypt: 0 ct-sta: 0'
[ 135.384426] ath10k_ahb a800000.wifi: wmi print 'free: 56528 iram: 23400 sram: 32520'
[ 135.486200] ath10k_ahb a800000.wifi: htt-ver 2.2 wmi-op 6 htt-op 4 cal pre-cal-file max-sta 32 raw 0 hwcrypto 1
[ 135.607114] ath: EEPROM regdomain: 0x0
[ 135.607125] ath: EEPROM indicates default country code should be used
[ 135.607128] ath: doing EEPROM country->regdmn map search
[ 135.607137] ath: country maps to regdmn code: 0x3a
[ 135.607142] ath: Country alpha2 being used: US
[ 135.607145] ath: Regpair used: 0x3a
[ 140.992286] ath: EEPROM regdomain: 0x8268
[ 140.992323] ath: EEPROM indicates we should expect a country code
[ 140.995385] ath: doing EEPROM country->regdmn map search
[ 141.001379] ath: country maps to regdmn code: 0x37
[ 141.006815] ath: Country alpha2 being used: PL
[ 141.011359] ath: Regpair used: 0x37
[ 141.015977] ath: regdomain 0x8268 dynamically updated by user
[ 141.019204] ath: EEPROM regdomain: 0x8268
[ 141.025098] ath: EEPROM indicates we should expect a country code
[ 141.029054] ath: doing EEPROM country->regdmn map search
[ 141.035189] ath: country maps to regdmn code: 0x37
[ 141.040508] ath: Country alpha2 being used: PL
[ 141.045130] ath: Regpair used: 0x37
[ 141.049532] ath: regdomain 0x8268 dynamically updated by user
[ 143.693904] ath10k_ahb a800000.wifi: 10.4 wmi init: vdevs: 16 peers: 48 tid: 96
[ 143.693960] ath10k_ahb a800000.wifi: msdu-desc: 2500 skid: 32
[ 143.729496] ath10k_ahb a800000.wifi: wmi print 'P 48/48 V 16 K 144 PH 176 T 186 msdu-desc: 2500 sw-crypt: 0 ct-sta: 0'
[ 143.730484] ath10k_ahb a800000.wifi: wmi print 'free: 56528 iram: 23400 sram: 32520'
[ 143.991721] ath10k_ahb a800000.wifi: Firmware lacks feature flag indicating a retry limit of > 2 is OK, requested limit: 4
[ 143.993186] IPv6: ADDRCONF(NETDEV_UP): wlanguest5: link is not ready
[ 144.017815] ath10k_ahb a800000.wifi: peer-unmap-event: unknown peer id 0
[ 144.017952] ath10k_ahb a800000.wifi: NOTE: Firmware DBGLOG output disabled in debug_mask: 0x10000000
[ 145.523591] ath10k_ahb a000000.wifi: 10.4 wmi init: vdevs: 16 peers: 48 tid: 96
[ 145.523645] ath10k_ahb a000000.wifi: msdu-desc: 2500 skid: 32
[ 145.559482] ath10k_ahb a000000.wifi: wmi print 'P 48/48 V 16 K 144 PH 176 T 186 msdu-desc: 2500 sw-crypt: 0 ct-sta: 0'
[ 145.560484] ath10k_ahb a000000.wifi: wmi print 'free: 56528 iram: 23400 sram: 32520'
[ 145.855672] ath10k_ahb a000000.wifi: Firmware lacks feature flag indicating a retry limit of > 2 is OK, requested limit: 4
[ 145.855922] IPv6: ADDRCONF(NETDEV_UP): wlanguest24: link is not ready
[ 147.341292] ath10k_ahb a800000.wifi: 10.4 wmi init: vdevs: 16 peers: 48 tid: 96
[ 147.341346] ath10k_ahb a800000.wifi: msdu-desc: 2500 skid: 32
[ 147.377047] ath10k_ahb a800000.wifi: wmi print 'P 48/48 V 16 K 144 PH 176 T 186 msdu-desc: 2500 sw-crypt: 0 ct-sta: 0'
[ 147.378046] ath10k_ahb a800000.wifi: wmi print 'free: 56528 iram: 23400 sram: 32520'
[ 147.645416] ath10k_ahb a800000.wifi: Firmware lacks feature flag indicating a retry limit of > 2 is OK, requested limit: 4
[ 147.645821] IPv6: ADDRCONF(NETDEV_UP): wlanguest5: link is not ready
[ 150.107251] IPv6: ADDRCONF(NETDEV_CHANGE): wlanguest24: link becomes ready
[ 213.146883] IPv6: ADDRCONF(NETDEV_CHANGE): wlanguest5: link becomes ready
[ 349.275320] ath10k_ahb a800000.wifi: peer-unmap-event: unknown peer id 0
[ 349.275366] ath10k_ahb a800000.wifi: peer-unmap-event: unknown peer id 0
[ 349.444393] ath10k_ahb a000000.wifi: mac-vif-chan had error in htt_rx_h_vdev_channel, peer-id: 0 vdev-id: 0 peer-addr: xx:xx:xx:xx:xx:xx.
[ 349.620423] ath10k_ahb a000000.wifi: peer-unmap-event: unknown peer id 0
[ 349.621033] ath10k_ahb a000000.wifi: peer-unmap-event: unknown peer id 0
[ 353.628992] ath10k_ahb a000000.wifi: 10.4 wmi init: vdevs: 16 peers: 48 tid: 96
[ 353.629039] ath10k_ahb a000000.wifi: msdu-desc: 2500 skid: 32
[ 353.665154] ath10k_ahb a000000.wifi: wmi print 'P 48/48 V 16 K 144 PH 176 T 186 msdu-desc: 2500 sw-crypt: 0 ct-sta: 0'
[ 353.666259] ath10k_ahb a000000.wifi: wmi print 'free: 56528 iram: 23400 sram: 32520'
[ 353.992891] ath10k_ahb a000000.wifi: Firmware lacks feature flag indicating a retry limit of > 2 is OK, requested limit: 4
[ 353.994796] IPv6: ADDRCONF(NETDEV_UP): wlanguest24: link is not ready
[ 354.008778] ath10k_ahb a000000.wifi: peer-unmap-event: unknown peer id 0
[ 355.525386] ath10k_ahb a000000.wifi: 10.4 wmi init: vdevs: 16 peers: 48 tid: 96
[ 355.525447] ath10k_ahb a000000.wifi: msdu-desc: 2500 skid: 32
[ 355.561480] ath10k_ahb a000000.wifi: wmi print 'P 48/48 V 16 K 144 PH 176 T 186 msdu-desc: 2500 sw-crypt: 0 ct-sta: 0'
[ 355.565152] ath10k_ahb a000000.wifi: wmi print 'free: 56528 iram: 23400 sram: 32520'
[ 355.967324] ath10k_ahb a000000.wifi: Firmware lacks feature flag indicating a retry limit of > 2 is OK, requested limit: 4
[ 355.969978] IPv6: ADDRCONF(NETDEV_UP): wlanguest24: link is not ready
[ 357.449140] ath10k_ahb a800000.wifi: 10.4 wmi init: vdevs: 16 peers: 48 tid: 96
[ 357.449192] ath10k_ahb a800000.wifi: msdu-desc: 2500 skid: 32
[ 357.485025] ath10k_ahb a800000.wifi: wmi print 'P 48/48 V 16 K 144 PH 176 T 186 msdu-desc: 2500 sw-crypt: 0 ct-sta: 0'
[ 357.488094] ath10k_ahb a800000.wifi: wmi print 'free: 56528 iram: 23400 sram: 32520'
[ 357.757015] ath10k_ahb a800000.wifi: Firmware lacks feature flag indicating a retry limit of > 2 is OK, requested limit: 4
[ 357.758512] IPv6: ADDRCONF(NETDEV_UP): wlanguest5: link is not ready
[ 360.245436] IPv6: ADDRCONF(NETDEV_CHANGE): wlanguest24: link becomes ready
[ 423.082884] IPv6: ADDRCONF(NETDEV_CHANGE): wlanguest5: link becomes ready
(notice very long pause between wlanguest24: link becomes ready and wlanguest5: link becomes ready.
ip a shows:
8: wlanguest24: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP qlen 1000
link/ether xx:xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff
inet 172.31.43.1/24 brd 172.31.43.255 scope global wlanguest24
valid_lft forever preferred_lft forever
inet6 fd3f:ba88:e212::1/64 scope global
valid_lft forever preferred_lft forever
inet6 fe80::2e3a:fdff:fe09:28bc/64 scope link
valid_lft forever preferred_lft forever
9: wlanguest5: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP qlen 1000
link/ether xx:xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff
inet6 fe80::2e3a:fdff:fe09:28bd/64 scope link
valid_lft forever preferred_lft forever
Sometimes it's the other way around: wlanguest5 is up, wlanguest24 is down.
Not sure how can I debug this and provide more information?