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gavinh
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Jumbo Frames causing Superhub 2ac to drop all internet access?

Hi guys,

I have just taken delivery of a shiny new Superhub 2ac, previously running quite happily with a Superhub at 100mbps (which will teach me never to be greedy again!).  Anyway, I have a Plex server running within my internal network. With the old Superhub I could connect remotely to it through the Plex application on my iPhone/ipad, all connected via a forwarded port 32400.  All super duper!

I have replicated that setup on the new Superhub 2ac. I have a port forward assigned for 32400 to redirect to the Plex server.  Now, when the Plex server fires up, it is running internally within my network quite happily.  All internet access is working fine.  The minute, and I mean the minute, I try to connect to the Plex server from a remote device (ie outside of my Virgin media network), all hell breaks lose!  The internet connection on the Superhub 2ac is dropped and no devices can access the internet.  The only solution is to reboot the Superhub 2ac each time, which isn't ideal and still leaves me with a Plex server that can't be accessed remotely.

I see there have been one or two other VirginMedia Superhub 2ac users on here with a similar issue.  Has anybody got to the bottom of this? 

Thanks

Gavin

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gavinh
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Re: Jumbo Frames causing Superhub 2ac to drop all internet access?

Well after disabling the Plex service, my network remained stable to 3hrs until my boys came back from school! They fired up their desktop PCs and were trying to launch www.faceit.com a gaming service! Another reboot of the cable modem and isolated test, the minute they try to access that WWW site, the Superhub 2ac crashed.

Now, I had an idea as to the cause of the problems. I disabled jumbo frames on my lads desktop machines and retried the connection attempt. Sure enough it worked OK and the Superhub remained stable.

So, taking this one step further I modified my NAS configuration to not use Jumbo Frames and restarted Plex application server. When I tried to connect to the Plex server using the application the Superhub 2ac remained stable and internet access was not affected! To me this smells like the Superhub 2ac can't handle Jumbo Frames correctly which causes a network crash.

Any thoughts?

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gavinh
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Re: Jumbo Frames causing Superhub 2ac to drop all internet access?

As a final test I put the Jumbo Frames back to 9K on the NAS and restarted the NAS.   I then tried to connect to the Plex Application server and <cough> down goes the internet.  To me it is clear the Superhub 2ac does not like playing with Jumbo Frames, but I can't prove any additional "technical log" information.  I have an engineer booked to come out on Thursday who, according to Virgin Media support assure me will be able to fix the issue....we shall see :-)

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gavinh
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Re: Jumbo Frames causing Superhub 2ac to drop all internet access?

Can a moderator change the title of this topic to read "Jumbo Frames
causing Superhub 2ac to drop all internet access?" Thanks :-)

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gavinh
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Re: Jumbo Frames causing Superhub 2ac to drop all internet access?

For the purposes of closure a VM engineer turned up this morning, turns out I had a Superhub 2, not a Superhub 2ac.  Anyway, I explained the problem, we swapped out the Superhub with a 2ac and I have just tried Jumbo frames setting again.  Success, with Jumbo Frames enabled the Superhub 2ac did not crash :-)

I'm happy to have got to the bottom of this.  Can I mod update the subject title of this topic to read "Jumbo Frames causing Superhub 2 to drop all internet access"?

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emailwoes
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Re: Jumbo Frames causing Superhub 2ac to drop all internet access?

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