AEBS: Bad Packets Unrecovered TCP Retransmits NV and NV+

[StephenB]

Ah... I asked the tech and he said as much, but then he seemed to think that the likely culprit is my NAS devices????

That is only possible if the NAS has two lan ports connected. (It would also need to be bridging between them.)

[paikinator@yahoo.com]

I think my problem is finally solved. Not the AEBS. Bad HP Procurve 1400-8G switch.
I have been running for 6 days with no errors.
Originally I do believe I had some bad cables which were contributing to my Bad Packets. Once I got the Cables all straitened out, the bad packets went away.
But then I had TCP retransmit problems. Now with the new switch, I get no more TCP retransmit errors.

Hewlett-Packard shipped replacement unit for my switch for free under their Procurve Lifetime Warranty. Awesome!

They didn't have any of the 1400 series on hand and so they shipped me a Procurve 1800-8G that looks to have been used, but is working beautifully. It is the managed version of what I had and would likely help me diagnose my problems more easily if something were to crop up in the future.

Thanks for all of the help.

[paikinator@yahoo.com]

Drat... I was able to induce more TCP retransmit errors even with the new switch.
It has been pretty stable, but I went to import a large number of photos from a shoot and at the same time I started moving some other big files.
TCP retransmits happened. I got about 8, but none failed upon retransmission... Then I got another 8 with 7 errors.
I guess I am at a loss.
Cables are all new Cat6 or Cat 6a so no new bad packets. Switch is a replacement for the other one which seemed to produce consistent errors. The errors went away, but I was able to choke the switch and it hung and I had to reboot it.

So I am guessing that something must not be playing nicely with my NAS devices or my NAS devices have a problem of some sort.
What could be wrong and how would I test it?
If I tread lightly and don't do too much at the same time on either NAS they seem to not produce TCP retransmit errors.
Perhaps this is what I need to do is deal with the flaws in the system. I can't really afford to replace everything right now. Boo.

Anyhow any suggestions or tips from anyone would be great. I will try limping along for now.
I don't believe the TCP retransmits will affect my file integrity if I am correct.
Does anybody see a problem with living with the problem? I am getting tired of working on it all.
Will I risk losing data? Could this cause me significant headaches?

[StephenB]

TCP retransmits will not hurt file integrity, so you can rest easy on that one. They will slow transfer speeds, but occasional retransmits are probably something you can live with.

You might look at the switch stats - keeping in mind that they generally report from the switch perspective (tx on the switch is rx on the NAS).

One possible cause is buffer overrun in the switch - since you were pushing a lot of data when you got the error. Look to see if 802.3x flow control is enabled on the switch. Also, if there are QOS settings, you can possibly prioritize traffic to/from the NAS.

Another possibility (generally rare these days) is that the switch thinks the link is half-duplex, but the NAS or PC thinks it is full duplex. If that is the case, you can usually manually override the setting on the switch.