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Old 07-11-2018, 02:21 AM   #16
business_kid
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5 months in hospital is beginning to tell on me.
The routes to 169.254.0.0 are probably routes crea by failed DHCP connections.

Is there a default route?

If the vm is dropping packets, that seems to be the source. Is anything showing download or upload errors? A dropped packet which is immediately retransmitted correctly is of much less consequence than errors.
 
Old 07-11-2018, 02:07 PM   #17
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Originally Posted by business_kid View Post
5 months in hospital is beginning to tell on me.
The routes to 169.254.0.0 are probably routes crea by failed DHCP connections.
It has to do with Automatic Private IP Addressing and I've now disabled it. I don't believe this has any bearing on the problem, however.

Quote:
Is there a default route?
Yes, of course. There would not be much networking without it.

Quote:
If the vm is dropping packets, that seems to be the source. Is anything showing download or upload errors? A dropped packet which is immediately retransmitted correctly is of much less consequence than errors.
The VM is dropping packets, but as I mentioned previously, every host (there are three) is dropping packets.

I don't see any indication in any logs that point to a cause or even that there are dropped packets.
 
Old 07-12-2018, 04:47 AM   #18
business_kid
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I'm now out of hospital, but not better. Ireland's hospitals leave much to be desired.

Roughly speaking, you have 600,000 packets dropped in 10.5 billion on the figures for eth0, roughly 0.06% (a figure not to be trusted). I'm out of ideas at the moment.
You seem to have done all the correct things. You haven't mentioned any errors, so I am presuming there are none. Doing those figures on other boxes may isolate the source, particularly if one box is having TX packets dropped. Maybe there is a way you could get those figures for the modem? The manufacturer may have something. Also, if the info is in many tiny transmissions as opposed to large lumps (hundred of megs) It could be dropping packets until speed adjusts.

EDIT: Trying again, I'm getting .006%

Last edited by business_kid; 07-12-2018 at 04:55 AM.
 
Old 07-12-2018, 11:02 AM   #19
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Quote:
Originally Posted by business_kid View Post
I'm now out of hospital, but not better. Ireland's hospitals leave much to be desired.

Roughly speaking, you have 600,000 packets dropped in 10.5 billion on the figures for eth0, roughly 0.06% (a figure not to be trusted). I'm out of ideas at the moment.
You seem to have done all the correct things. You haven't mentioned any errors, so I am presuming there are none. Doing those figures on other boxes may isolate the source, particularly if one box is having TX packets dropped. Maybe there is a way you could get those figures for the modem? The manufacturer may have something. Also, if the info is in many tiny transmissions as opposed to large lumps (hundred of megs) It could be dropping packets until speed adjusts.

EDIT: Trying again, I'm getting .006%
Thanks for your help, and hope you recover quickly. I was also in the hospital for quite some time here in the US.

I recently was reminded about netstat and found some stats that are informative:

Code:
# netstat -s|grep -Ei 'drop|fail'
    933 outgoing packets dropped
    72 dropped because of missing route
    1 fragments dropped after timeout
    1 packet reassemblies failed
    226848 input ICMP message failed
    0 ICMP messages failed
    54988 failed connection attempts
    2153 ICMP packets dropped because they were out-of-window
    329 SYNs to LISTEN sockets dropped
    TCPSackFailures: 252
    TCPSackRecoveryFail: 239
    TCPDeferAcceptDrop: 105588
I'm trying to determine why these packets were dropped.
 
Old 07-14-2018, 12:55 PM   #20
business_kid
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In 10 billion packets, I would ignore figures under 1000. That leaves
Code:
226848 input ICMP message failed
54988 failed connection attempts
TCPDeferAcceptDrop: 105588
2153 ICMP packets dropped because they were out-of-window
If we ignore failed connection attempts, as they are possible on any system and aren't necessarily failures in your box, the big one is ICMP (basically error messages). I'll leave it to you to decide how important they are.
 
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