ICMP inop

[Garrett Williamson]

Having an issue with icmp on my galaxy s8.
I use a generic network analyzer, and also terminux (terminal emulator) to run pings and traceroutes on occasion.
All of a sudden, both are failing completely. I can ping my loopback 127.0.0.1, but i cant get to my default gateway, google, google dns server, nothin'. This is over wifi, verizons towers, even hardwired with usb-c to rj45.
Interestingly, internet is unaffected. Works fine.

...any ideas?

 

[svim]

Having an issue with icmp on my galaxy s8.
I use a generic network analyzer, and also terminux (terminal emulator) to run pings and traceroutes on occasion.
All of a sudden, both are failing completely. I can ping my loopback 127.0.0.1, but i cant get to my default gateway, google, google dns server, nothin'. This is over wifi, verizons towers, even hardwired with usb-c to rj45.
Interestingly, internet is unaffected. Works fine.

...any ideas?

Well if your Internet access is unaffected and you're referring to Verizon towers, how are you determining that you're not getting online access through your cellular connectivity and not WiFi connectivity? By all indications it sounds like you're having an issue with your LAN.
Have you rebooted your modem, your router, and your phone? That's the first thing to try just to eliminate any one-off networking glitch. If the problem remains after everything is restarted at least you know there's a repeatable problem to look for. And just to save a lot of repetition, just what have you tried to address the problem?

 

[Garrett Williamson]

Well if your Internet access is unaffected and you're referring to Verizon towers, how are you determining that you're not getting online access through your cellular connectivity and not WiFi connectivity? By all indications it sounds like you're having an issue with your LAN.
Have you rebooted your modem, your router, and your phone? That's the first thing to try just to eliminate any one-off networking glitch. If the problem remains after everything is restarted at least you know there's a repeatable problem to look for. And just to save a lot of repetition, just what have you tried to address the problem?

Hey, thanks for the reply.

So the problem is occurring whatever network I attach to. If my wifi is disabled and i'm only on verizon towers, on wifi at my house, wifi at my friends house across town. Hardwired to the modem, same deal.

Troubleshooting so far:

Rebooted phone several times.

Confirmed latest software update installed.

Tried multiple programs. (Terminal emulator and network analyzer)

Confirmed able to ping loopback.

Tried pinging different servers, yahoo, google, 8.8.8.8, default gateway.

Tried on multiple different networks. (Walmarts wifi, home wifi, cell network well away from any wifi networks, hardwired to a friends modem across town)

Tried increasing timeout threshold for ping.

Checked cpu utilization, checked memory use, checked app permissions, closed all open programs besides the one I was using.

Another interesting note, the issue seems to be coming and going. Generelly it just doesnt work, but a handful of times, pings just start going through normally. For maybe 5 minutes. Then back to square one.

And yeah my first thought was a problem on the LAN, but I've pretty well ruled that out unfortunately.

Where else would you look if you were me?

Update: it has been working this morning consistently the last 15 minutes. I realized I was on power save mode yesterday. Power save mode is off now. Odd that it would have an effect on something like that, but could also be a coincidence. I'll keep fooling with it today, see if it acts up.

Pretty conclusive: medium power save mode causes issues with icmp. Really not sure why that would be.
Pinging away all day no problem. Switch on power save mode, ping fails.
Switch it off, works fine again. Well at least now I know.

 

[svim]

Ahhh, OK so it is just an issue where no matter how you're getting an online connection, the problem is there. That does tend to indicate an issue with your phone. Somewhere in your phone's Settings >> Wireless & networks menu there should be a 'Network settings reset' option. You might want to try that but note it's pretty much a nuclear option for networking settings -- it not only resets your WiFi and cellular to their defaults but it also wipes things like any saved WiFi SSID entries, Bluetooth pairings you've saved, any changes you made to app data restrictions, etc,