MP 1,1-5,1 Weird internet connectivity issue with Mac Pro 5,1?

[rstreber]

For the past few months, I've had a strange problem with unusably-slow internet speeds on my Mid 2012 Mac Pro running 10.14.6. The machine is the primary for my commercial recording studio (we run a Pro Tools HDX system that's PCIe based, and so the old Mac Pro continues to be a stable work horse.)

I send relatively large files daily to clients and had been relying on Google Drive for this. However, seemingly out of the blue, I became unable to upload even tiny files with Google Drive. At first I thought that maybe it was an issue with a Google / Chrome software update causing problems with Mojave. However, most other sites as well will load but then I can't download anything (even small email attachments.). Or a video on youtube will start to play and then freeze. This is the same regardless of browser (at least I've tried Chrome, Safari, and Firefox.) I've also tried connecting both via ethernet and WiFi. Same behavior.

If I run speed test, it shows around 300mb up and down as should be expected (we have FiOS service here.)

What's really strange is that WeTransfer works perfectly and fast. I can easily upload and download gigs worth of data at speeds corresponding to what speed test shows. I can also upload and transfer files as normal if using my current era Macbook pro connected to this machine via local network.

I'm stumped - any suggestions or areas to investigate that I might be missing?

 

[ppinter1]

Just a shot in the dark, but I'd enable the 2nd Ethernet controller on your MacPro and try using that instead?

Otherwise, signs point to Drive as the culprit.

 

[rstreber]

I can try that. We run our whole studio on a Dante network (audio over local network) which is connected to the 2nd ethernet port, so I've tried to not mess with it. But I can see if the 2nd one makes a difference. The fact that the problem is the same with WiFi makes me feel like that's not the issue though. And I was convinced for while that it was a Drive issue, but then realizing that I can't play a Youtube video or a song on Spotify made me question that assumption...

 

[IngoX]

Another shot in dark, but check if there is a manual MTU set for the network interfaces. Perhaps you have tweaked it for your internal network? But I guess automatic (1500?) is safest for internet services.

 

[ppinter1]

Another WAG: While an outage on Drive or Google-owned Spotify/YouTube would be headline news, it's conceivable you have a local plumbing problem. I.E. borkage on your local path to Google's highly ubiquitous servers.

Maybe try:

• a 'dig drive.google.com' command and record the IPv4 address from the A record
• a 'dig -t AAAA drive.google.com' command and record the IPv6 address from the AAAA record

Then, try a ping command on the IPv4 address. Here, my pings fail with a timeout. Odd.
Also, try a ping6 command on the IPv6 address. Here, my ping6s reply within ~20ms.

When I try a traceroute command on the IPv4 address, the path stalls for 8 hops before a 20ms response. Hmmm.
When I try a traceroute6 command on the IPv6 address, it's only 3 hops to Seattle for a 20ms response.

Just thinking out loud here.

 

[rstreber]

Thanks so much for this - I'm not super savvy when it comes to this stuff, but hopefully I can figure out how to run those commands correctly. I guess the question is what to do about it if something does seem amiss?

An example of how this is so weird: right now, I'm doing a session with a remote attendee and streaming relatively high-quality audio to a listener on the west coast from this same computer via audio movers, and it's working fine. So maybe it does have to do with Google servers as you say, rather than just G-Suite specifically...

 

[rstreber]

Just bumping this thread... when I ping the Google IPv4 I get times between 2.9ms and 8.25ms. When I try to ping the IPv6, I get "cannot resolve... unknown host." Same result if I run the traceroute command on the IPv6 address - it says unknown host. Any suggestions on what that might mean or what I might try to get a different result?

Again, I just downloaded and installed a multi-gig software installer package from one software vendor in about 45 seconds. With a different vendor, the download stalled at 3 mb and was showing download speeds of around 350 kb/s. Neither of these vendors were Google, but I'm wondering if one uses Google servers and the other doesn't?

 

[ppinter1]

Well, first I'm jealous of your Fios. My ISP still uses a carrier pigeon based backbone, with smoke signals for backup.

Anyway, maybe flush the DNS cache, which on 10.14 Mojave is: sudo killall -HUP mDNSResponder and try the pings again - both to the Google Drive IP address and the 2nd (stalling) vendor - and see what, if anything, changes.

 

[rstreber]

Thanks - FiOS has been great which is why it's especially crazy-making having these slow speeds with like half of the internet just on this one computer. I tried running that DNS cache flush command and re-pinging, and I got the same results.

 

[ppinter1]

The last thing I'd try before running off to join the circus: disable IPv6 in System Preferences->Network (taking a photo of current settings first) to force traffic onto IPv4. Reboot and re-test. If still no joy, restore previous settings and call it a day. I'm out of ideas

 

[rstreber]

Looking at system prefs for both the Ethernet connectors as well as WiFi, I don't have an optino to turn IPv6 off. Under advanced / TCP/IP, I see the Configure IPv4 and Configure IPv6 tabs. the v4 tab has an "off" option, but v6 just has options for Auto, Manual, or Link-local only. Am I missing something? (pardon my dumb questions in advance, and thanks for your help!!)

 

[ppinter1]

Sorry, my fault. I'm nowhere near a Mac today and was going on (faulty) memory.

Yes it's the 'Link Local' setting you want to try. It's likely set to Auto now, but if not, record the details to restore afterwards.

 

[h9826790]

Looking at system prefs for both the Ethernet connectors as well as WiFi, I don't have an optino to turn IPv6 off. Under advanced / TCP/IP, I see the Configure IPv4 and Configure IPv6 tabs. the v4 tab has an "off" option, but v6 just has options for Auto, Manual, or Link-local only. Am I missing something? (pardon my dumb questions in advance, and thanks for your help!!)

In general, leave it automatic should has no address (which means it's practically off). But you can switch to link-local only, that will also stop the Mac to use IPv6 for the interenet.

Or you may config the router to stop using IPv6.

 

[rstreber]

Wow, changing IPv6 to Link-local only did it! I just uploaded a folder to Google drive with no issues for the first time in months, and the download from the software vendor that wouldn't get passed a few megs yesterday just did a 5Gb download in a few minutes! Now the question is, should I leave IPv6 off and call it good, or is there anything else I should try from here? Regardless, thanks so much for your help!!

 

[h9826790]

Wow, changing IPv6 to Link-local only did it! I just uploaded a folder to Google drive with no issues for the first time in months, and the download from the software vendor that wouldn't get passed a few megs yesterday just did a 5Gb download in a few minutes! Now the question is, should I leave IPv6 off and call it good, or is there anything else I should try from here? Regardless, thanks so much for your help!!

I think you better leave it alone. IPv4 still the main stream today.

 

[ppinter1]

Glad to hear it!

If there's one thing I've learned after 45 years as a programmer, it's "Just give it what it wants!".

While IPv6 networking will eventually be the default for all kinds of excellent reasons, we're not there yet.

So, unless you diagnose why your premise router is griefing your Mojave-vintage IPv6 implementation, I'd leave the bastige alone and go for beers. Whuzzzaaaaaaa!🍻