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I am running Raspbian 11 on Pi Zero W. I use the built in wifi. The board is new with freshly installed OS. Issues have been present from the outset.

I can connect to my home wifi with no issues. But the connection is unstable. VNC disconnects after seconds or minutes. Package downloads time out unpredictably.

Ping results are also unpredictable. Here I have no issues:

pi@raspberrypi2:~ $ ping google.com
PING google.com(sfo07s13-in-x0e.1e100.net (2607:f8b0:4005:804::200e)) 56 data bytes
64 bytes from sfo07s13-in-x0e.1e100.net (2607:f8b0:4005:804::200e): icmp_seq=1 ttl=58 time=97.1 ms
64 bytes from sfo07s13-in-x0e.1e100.net (2607:f8b0:4005:804::200e): icmp_seq=2 ttl=58 time=17.1 ms
64 bytes from sfo07s13-in-x0e.1e100.net (2607:f8b0:4005:804::200e): icmp_seq=3 ttl=58 time=15.7 ms
64 bytes from sfo07s13-in-x0e.1e100.net (2607:f8b0:4005:804::200e): icmp_seq=4 ttl=58 time=15.0 ms
64 bytes from sfo07s13-in-x0e.1e100.net (2607:f8b0:4005:804::200e): icmp_seq=5 ttl=58 time=14.8 ms
64 bytes from sfo07s13-in-x0e.1e100.net (2607:f8b0:4005:804::200e): icmp_seq=6 ttl=58 time=13.8 ms
64 bytes from sfo07s13-in-x0e.1e100.net (2607:f8b0:4005:804::200e): icmp_seq=7 ttl=58 time=16.2 ms
64 bytes from sfo07s13-in-x0e.1e100.net (2607:f8b0:4005:804::200e): icmp_seq=8 ttl=58 time=81.3 ms
64 bytes from sfo07s13-in-x0e.1e100.net (2607:f8b0:4005:804::200e): icmp_seq=9 ttl=58 time=31.1 ms
64 bytes from sfo07s13-in-x0e.1e100.net (2607:f8b0:4005:804::200e): icmp_seq=10 ttl=58 time=14.7 ms
64 bytes from sfo07s13-in-x0e.1e100.net (2607:f8b0:4005:804::200e): icmp_seq=11 ttl=58 time=14.9 ms
64 bytes from sfo07s13-in-x0e.1e100.net (2607:f8b0:4005:804::200e): icmp_seq=12 ttl=58 time=16.1 ms
64 bytes from sfo07s13-in-x0e.1e100.net (2607:f8b0:4005:804::200e): icmp_seq=13 ttl=58 time=16.0 ms
64 bytes from sfo07s13-in-x0e.1e100.net (2607:f8b0:4005:804::200e): icmp_seq=14 ttl=58 time=14.7 ms
64 bytes from sfo07s13-in-x0e.1e100.net (2607:f8b0:4005:804::200e): icmp_seq=15 ttl=58 time=47.3 ms
64 bytes from sfo07s13-in-x0e.1e100.net (2607:f8b0:4005:804::200e): icmp_seq=16 ttl=58 time=19.8 ms
64 bytes from sfo07s13-in-x0e.1e100.net (2607:f8b0:4005:804::200e): icmp_seq=17 ttl=58 time=15.2 ms
64 bytes from sfo07s13-in-x0e.1e100.net (2607:f8b0:4005:804::200e): icmp_seq=18 ttl=58 time=69.4 ms
64 bytes from sfo07s13-in-x0e.1e100.net (2607:f8b0:4005:804::200e): icmp_seq=19 ttl=58 time=25.9 ms
^C
--- google.com ping statistics ---
19 packets transmitted, 19 received, 0% packet loss, time 18026ms
rtt min/avg/max/mdev = 13.800/29.271/97.095/24.791 ms

But shortly after, ping fails:

pi@raspberrypi2:~ $ ping google.com
ping: google.com: Temporary failure in name resolution

I can usually ping another pi zero on my local network. (connected over wifi)

pi@raspberrypi2:~ $ ping 192.168.1.109
PING 192.168.1.109 (192.168.1.109) 56(84) bytes of data.
64 bytes from 192.168.1.109: icmp_seq=1 ttl=64 time=1114 ms
64 bytes from 192.168.1.109: icmp_seq=2 ttl=64 time=67.0 ms
64 bytes from 192.168.1.109: icmp_seq=3 ttl=64 time=23.9 ms
64 bytes from 192.168.1.109: icmp_seq=4 ttl=64 time=9.33 ms
64 bytes from 192.168.1.109: icmp_seq=5 ttl=64 time=11.2 ms
64 bytes from 192.168.1.109: icmp_seq=6 ttl=64 time=7.41 ms
64 bytes from 192.168.1.109: icmp_seq=7 ttl=64 time=7.18 ms
64 bytes from 192.168.1.109: icmp_seq=8 ttl=64 time=47.9 ms
64 bytes from 192.168.1.109: icmp_seq=9 ttl=64 time=12.2 ms
^C
--- 192.168.1.109 ping statistics ---
9 packets transmitted, 9 received, 0% packet loss, time 8057ms
rtt min/avg/max/mdev = 7.184/144.464/1114.139/343.396 ms, pipe 2

But sometimes that fails:

pi@raspberrypi2:~ $ ping 192.168.1.109
PING 192.168.1.109 (192.168.1.109) 56(84) bytes of data.
From 192.168.1.133 icmp_seq=9 Destination Host Unreachable
From 192.168.1.133 icmp_seq=10 Destination Host Unreachable
From 192.168.1.133 icmp_seq=11 Destination Host Unreachable
From 192.168.1.133 icmp_seq=12 Destination Host Unreachable
From 192.168.1.133 icmp_seq=13 Destination Host Unreachable
From 192.168.1.133 icmp_seq=14 Destination Host Unreachable
From 192.168.1.133 icmp_seq=15 Destination Host Unreachable
From 192.168.1.133 icmp_seq=16 Destination Host Unreachable
From 192.168.1.133 icmp_seq=17 Destination Host Unreachable
^C
--- 192.168.1.109 ping statistics ---
20 packets transmitted, 0 received, +9 errors, 100% packet loss, time 19739ms
pipe 4

Attempts to ping my Windows PC (connected over ethernet) always fail:

pi@raspberrypi2:~ $ ping 192.168.1.143
PING 192.168.1.143 (192.168.1.143) 56(84) bytes of data.
^C
--- 192.168.1.143 ping statistics ---
11 packets transmitted, 0 received, 100% packet loss, time 10382ms

When I continuously ping the pi from my Windows PC I get occasional request timed out:

Reply from 192.168.1.133: bytes=32 time=5ms TTL=64
Reply from 192.168.1.133: bytes=32 time=3ms TTL=64
Reply from 192.168.1.133: bytes=32 time=4ms TTL=64
Request timed out.
Reply from 192.168.1.133: bytes=32 time=2ms TTL=64
Reply from 192.168.1.133: bytes=32 time=5ms TTL=64
Reply from 192.168.1.133: bytes=32 time=5ms TTL=64
Reply from 192.168.1.133: bytes=32 time=3ms TTL=64
Reply from 192.168.1.133: bytes=32 time=5ms TTL=64
Reply from 192.168.1.133: bytes=32 time=4ms TTL=64
Reply from 192.168.1.133: bytes=32 time=3ms TTL=64
Reply from 192.168.1.133: bytes=32 time=4ms TTL=64
Reply from 192.168.1.133: bytes=32 time=3ms TTL=64
Reply from 192.168.1.133: bytes=32 time=2ms TTL=64
Reply from 192.168.1.133: bytes=32 time=5ms TTL=64
Reply from 192.168.1.133: bytes=32 time=4ms TTL=64
Reply from 192.168.1.133: bytes=32 time=2ms TTL=64
Reply from 192.168.1.133: bytes=32 time=3ms TTL=64
Reply from 192.168.1.133: bytes=32 time=6ms TTL=64
Reply from 192.168.1.133: bytes=32 time=8ms TTL=64
Reply from 192.168.1.133: bytes=32 time=2ms TTL=64
Reply from 192.168.1.133: bytes=32 time=2ms TTL=64
Reply from 192.168.1.133: bytes=32 time=2ms TTL=64

Ping statistics for 192.168.1.133:
    Packets: Sent = 123, Received = 122, Lost = 1 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 2ms, Maximum = 36ms, Average = 5ms

The Pi wifi signal strength never drops below -50 dBm.

Wavemon utility stalls during ping failures, shows n/a for TX/RX stats and frequency/channel:

┌─Interface─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│wlan0 (IEEE 802.11), phy 0, reg: US (DFS-FCC), SSID: betterwork                                                                │
├─Levels────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┤
│                                                                                                                               │
│link quality: 91%  (64/70)                                                                                                     │
│====================================================================================================================           │
│                                                                                                                               │
│                                                                                                                               │
│signal level: -46 dBm (0.03 uW)                                                                                                │
│============================================================================                                                   │
│                                                                                                                               │
├─Statistics────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┤
│RX: n/a                                                                                                                        │
│TX: n/a                                                                                                                        │
├─Info──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┤
│mode: Managed, connected to: C4:41:1E:1E:40:48, time: 0 sec, inactive: 0.0s                                                    │
│frequency/channel: n/a                                                                                                         │
│rx rate: 1.0 Mbit/s, tx rate: 72.2 Mbit/ss                                                                                     │
│station flags: (none), preamble: short, slot: long                                                                             │
│power mgt: off                                                                                                                 │
│retry: short limit 7,  rts/cts: off,  frag: off                                                                                │
├─Network───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┤
│wlan0 (UP RUNNING BROADCAST MULTICAST)                                                                                         │
│mac: B8:27:EB:AD:D7:A7, qlen: 1000                                                                                             │
│ip: 192.168.1.133/24 

I don't have noticeable wifi issues on other devices. The router is new - Linksys Dual Band Wifi 5 router, EA7200

Can anyone suggest troubleshooting steps?

Edit: GUI taskbar sometimes shows the wifi icon with full bars. Other times it shows up/down arrows and "No APs found - scanning..." even while VNC connection is alive. Seems like a bug. VNC should disconnect of no APs are detected. Not sure what to make of this.

2
  • does the "other pi zero" also suffer the same issue?
    – Bravo
    Feb 14, 2022 at 22:55
  • @Bravo I experience some of the same issues on the other pi zero. It's running Raspbian 8. I suppose that points towards a router issue. But I don't experience disconnections on a windows laptop connected to wifi. I'm planning to try a wifi dongle for the pi zero.
    – Dylan Kane
    Feb 15, 2022 at 16:57

1 Answer 1

2

I happen to be seeing the same thing on occasion. I can't quite prove it yet but I suspect (and seen others complain) that possibly this is related to the WiFi controller power_save feature.

You can try to check the state of power management:

sudo iw wlan0 get power_save

try toggling it off:

sudo iw wlan0 set power_save off

and see if it helps.

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