Re: 60+% ping packet loss on Pi3 under -current and stable-13

From: bob prohaska <fbsd_at_www.zefox.net>
Date: Mon, 02 May 2022 01:13:12 UTC
On Sun, May 01, 2022 at 05:10:59PM -0700, Mark Millard wrote:
[reply at end]
> On 2022-May-1, at 16:27, bob prohaska <fbsd@www.zefox.net> wrote:
> 
> > On Sun, May 01, 2022 at 12:58:45PM -0700, Mark Millard wrote:
> >> 
> >> Looks like there is some problem getting past
> >> gig1-1-1.gw.davsca11.sonic.net .
> >> 
> > 
> > That seems independent of my own internal connection problems,
> > but worth taking up with my ISP on Monday. Meanwhile, can you
> > ping any other hosts in the 50.1.20.31-24 range? All are up
> > at the moment. Hosts 28 and 24 are the troublemakers. 
> > 
> > If anybody cares there's an ascii-art network diagram at
> > http://www.zefox.net/~fbsd/netmap
> > 
> > Not sure it'll survive the mailing list, but here goes:
> > dsl_modem-----switch---------router-----lan-------wifi-----pi4_workstation
> >                      |                  |             | 
> >                      |                  |             |---Mac workstation
> >                      |                  |
> >                      |                  |------printer
> >    ------------------|
> >    |
> >    |------50.1.20.30 ns1.zefox.net Pi2 12.3 usb-serial----50.1.20.27
> >    |------50.1.20.29 ns2.zefox.net Pi2 12.3 usb-serial----50.1.20.30
> >    |------50.1.20.27 www.zefox.net Pi2 12.3 usb-serial----50.1.20.26
> >    |------50.1.20.26 www.zefox.com Pi2 -current usb-serial---50.1.20.24
> >    |------50.1.20.24 pelorus.zefox.org Pi3 13.1 usb-serial---50.1.20.28
> > switch
> >    |------50.1.20.25 nemesis.zefox.com Pi4 -current usb-serial---50.1.20.29
> >    |------50.1.20.28 www.zefox.org Pi3 -current usb-serial----50.1.20.25
> 
> 
> For ns1.zefox.net there is no problem and
> it looks like:
> 
>                                      My traceroute  [v0.95]
> amd64_ZFS (192.168.1.120) -> ns1.zefox.net (50.1.20.29)                2022-05-01T16:52:27-0700
> Keys:  Help   Display mode   Restart statistics   Order of fields   quit
>                                                        Packets               Pings
>  Host                                                Loss%   Snt   Last   Avg  Best  Wrst StDev
>  1. 192.168.1.1                                       0.0%    53    1.2   0.8   0.1   1.4   0.4
>  2. 172.30.26.67                                      0.0%    53   11.8  25.0  11.8  61.0  11.4
>  3. 68.85.243.125                                     0.0%    53   10.0  10.0   7.7  46.9   5.3
>  4. 96.216.60.165                                     0.0%    53    8.8   9.3   7.8  12.1   0.9
>  5. 68.85.243.197                                     0.0%    53    8.6  13.2   8.6  28.3   4.2
>  6. be-36231-cs03.seattle.wa.ibone.comcast.net        0.0%    53   15.3  14.8  13.0  16.9   1.0
>  7. be-2312-pe12.seattle.wa.ibone.comcast.net         0.0%    53   16.2  15.9  12.9  59.8   6.5
>  8. (waiting for reply)
>  9. be3717.ccr22.sfo01.atlas.cogentco.com             0.0%    53   29.8  30.9  26.5  97.9  10.1
> 10. be2430.ccr31.sjc04.atlas.cogentco.com             0.0%    53   29.0  29.0  26.6  39.3   1.8
> 11. 38.104.141.82                                     0.0%    53   28.9  33.8  26.1 115.0  17.0
> 12. 0.xe-0-3-0.scrm-gw1.scrmca01.sonic.net            0.0%    53   32.1  31.3  29.2  33.9   1.0
> 13. 0.xe-0-0-0.cr1.scrmca13.sonic.net                 0.0%    53   30.5  32.1  29.2  57.6   4.3
> 14. gig1-1-1.gw.wscrca11.sonic.net                    0.0%    53   31.8  32.0  28.8  43.7   2.0
> 15. gig1-1-1.gw.davsca11.sonic.net                    0.0%    52   31.0  32.4  30.2  38.4   1.4
> 16. ns1.zefox.net                                     0.0%    52   51.4  51.1  49.8  53.4   0.8
> 
> ns2.zefox.net and others got a 17. instead of
> a 16. An example is:
> 
>                                      My traceroute  [v0.95]
> amd64_ZFS (192.168.1.120) -> ns2.zefox.net (50.1.20.30)                2022-05-01T16:58:45-0700
> Keys:  Help   Display mode   Restart statistics   Order of fields   quit
>                                                        Packets               Pings
>  Host                                                Loss%   Snt   Last   Avg  Best  Wrst StDev
>  1. 192.168.1.1                                       0.0%    55    0.3   0.9   0.1   1.4   0.4
>  2. 172.30.26.66                                      0.0%    55   13.5  26.4  10.4  54.7  10.1
>  3. 68.85.243.77                                      0.0%    55   10.5   9.1   7.9  10.5   0.6
>  4. 24.124.129.106                                    0.0%    54    8.3   9.5   8.2  13.4   1.0
>  5. 96.216.60.165                                     0.0%    54    8.8   9.8   7.8  22.8   2.2
>  6. 68.85.243.197                                     0.0%    54   17.1  15.1   9.0  37.3   5.9
>  7. be-36241-cs04.seattle.wa.ibone.comcast.net        0.0%    54   15.2  15.0  13.2  17.8   0.9
>  8. be-2412-pe12.seattle.wa.ibone.comcast.net         0.0%    54   15.0  14.8  13.2  17.1   1.0
>  9. (waiting for reply)
> 10. be2075.ccr21.sfo01.atlas.cogentco.com             0.0%    54   28.4  29.2  26.9  36.8   1.4
> 11. be2379.ccr31.sjc04.atlas.cogentco.com             0.0%    54   29.8  30.0  27.3  84.2   7.6
> 12. 38.104.141.82                                     0.0%    54   28.6  33.7  27.5 105.5  16.2
> 13. 0.xe-0-3-0.scrm-gw1.scrmca01.sonic.net            0.0%    54   31.6  31.4  29.5  33.8   0.9
> 14. 0.xe-0-0-0.cr1.scrmca13.sonic.net                 0.0%    54   31.1  32.1  29.1  52.9   3.4
> 15. gig1-1-1.gw.wscrca11.sonic.net                    0.0%    54   31.2  31.9  30.0  34.1   0.9
> 16. gig1-1-1.gw.davsca11.sonic.net                    0.0%    54   33.3  32.6  30.8  45.8   2.1
> 17. ns2.zefox.net                                     0.0%    54   52.5  51.4  49.1  54.9   1.2
> 
> The routing need not be the same from one
> try to the next.
> 
> www.zefox.net     is similar.
> www.zefox.com     is similar.
> pelorus.zefox.org is similar.
> nemesis.zefox.com is similar.
> www.zefox.org     is similar.
> 
> Notably www.zefox.org was what I tried and
> reported on before that had the failures.
> 
> I observed a initial connection sequence once
> for pelorus.zefox.org where it briefly displayed
> something like (not captured, just from memory):
> 
> 16. gig1-1-1.gw.davsca11.sonic.net
> 17. (waiting for reply)
> 18. (waiting for reply)
> 19. pelorus.zefox.org
> 
> before changing to
> 
> 16. gig1-1-1.gw.davsca11.sonic.net
> 17. ns2.zefox.net
> 
> That may be normal but usually timed such that I
> would not usually see it.
> 
> But it might actually be evidence of a stage that
> the leads to the overall failure by never getting
> past the:
> 
> 16. gig1-1-1.gw.davsca11.sonic.net
> 17. (waiting for reply)
> 18. (waiting for reply)
> 19. WHATEVER
> 
> in some cases.
> 
> However, in the above the below worked fine:
> 
> 50.1.20.24 pelorus.zefox.org Pi3 13.1 usb-serial---50.1.20.28
> 50.1.20.28 www.zefox.org Pi3 -current usb-serial----50.1.20.25
> 
> What changed?

I restarted an outgoing ping so I could access those hosts via ssh, 
to bring up a serial console connection to the next host in the "ring". 
Usually I simply ping 50.1.20.31 (my router) but at least in the past
it did not matter what the destination was. In one case I tried an
unused address. That makes the role of a distant host somewhat
baffling.

Thanks for checking!

bob prohaska

> 
> 
> ===
> Mark Millard
> marklmi at yahoo.com
> 
>