Ethernet connection dropping out every 10 mins

 I don't understand your ethernet circuit & where the switch is installed.  "connection from iMac to router is Ethernet cable. Then another ethernet to ND5, via a 'switch'.   In a normal LAN that is not the place for a network switch.  

But most puzzling  - what is a 'switch' when the word is between ' '

The connection sequence should be:

• ISP router > switch
• All networked gear plugged into the switch (i.e. Mac, streamer, etc)

IP addresses should assigned by the router automatically.

@ Mike - do you have that simple picture to illustrate the connections?

Of course,  but I am still intrigued by what is a " 'switch' "

Hi, sound strange if you haven't adjusted any of the cables. It might be worth power cycling the switch if you haven't already . I had a llittle Netgear switch that became unstable  with layer 2 (MAC) addresses recently for some obscure reason  that was remedied with powering on and off, and it's been fine since... an outside chance but you never know.

Simon

Mike-B posted:

Of course,  but I am still intrigued by what is a " 'switch' "

 

The OP will no doubt tell us, but one reason for having a switch not in the place where you suggest may be that there are other things connected to the network via the switch and with the iMac in a different part of the house to the NDS. For example that is what happens in my house (except I don't have a Mac or an NDS!)

I do agree with Simon's suggestion to restart the switch (which should only take 10 secs or so) and the other thing I would try if that doesn't fix it is re-starting the router. Depending on the router, restarting it may necessitate restarting everything else so as to avoid IP clashes, but some routers just reassign the same IP addresses to MAC addresses they recognise. So I suggest the OP tries it and sees what happens.....

best

David

Hi Simon

I have powered down the switch, router, and ND5. Wi-Fi is fine though!! There has been lots of discussion on the forum about DHPC, to which the router is set to. What is the optimum setting of the router for the ND5?

Davina

FWIW I had exactly the same problem last week.  Both internet and network up and down like a yo-yo. Thought router was faulty and was about to buy a new one.  Mrs JSH suggested I rang BT.  Turned out that Openreach were digging the road up to lay new cable a mile or two away and everyone's internet was up and down.  Seems that the effect was that the Openreach drop-outs/resets seemed to lead the router to keep re-setting and when it did the network went down.  Back to normal this week.

Now I'm not an expert like Simon and others but you might want to check with your ISP and give it a day or two

Davina60 posted:

Hi Simon

I have powered down the switch, router, and ND5. Wi-Fi is fine though!! There has been lots of discussion on the forum about DHPC, to which the router is set to. What is the optimum setting of the router for the ND5?

 

Davina

Leave it the DHCP mode and ND5XS in the  network settings with DHCP = YES

Thank you everyone. I know it sounds crazy, but in my Mac's 'Network Preferences' there was a box called "Renew DHCP Lease". I ticked that, and system is behaving it self at the moment. No idea if that sorted it??

Hi Mike..Thank you for your reply.

Ethernet from iMac to router, Ethernet from router to switch, Ethernet from switch to ND5 XS. It's been perfect for a year...then suddenly last night! Funnily enough, it's been ok for the past hour. Router is set to DHCP server.

The problem is at the Mac end, as Wi-Fi is just fine on my iPad and phone.

davina

Mike-B posted:

Of course,  but I am still intrigued by what is a " 'switch' "

 

Sorry Mike, I just meant a switch. 

I correct my first post. Mac to switch, router to switch, switch to ND5. 

The system is behaving at the moment, but all throughout the day, the Mac was not Receiving the internet via the Ethernet connection. 

I am am of course wondering, does the system actually need the Internet connection in order to stream? If the answer is no, then perhaps there is a fault with the Audioquest Ethernet cable  from the Mac to the switch, which is conveying the music to the ND5.

Router >>> Switch >>> everything else plugged into switch (which looking at your last post seems to be what you have) and you don't need internet to stream/play the music on your server.  Maybe if your routers internet connection was being reset repeatedly due to some work by BT Openreach at the exchange or junction box, that may mess things up on your home network because the router may be restarting and sending out IP's to everything on your network.

I've not been with Sky for a while now, over a year, but their router Ethernet connections used to be fast Ethernet, 100Mb.  Your switch may be Gigabit Ethernet speed (1000Mb).  Before I bought myself a Gigabit switch, when I transferred a lot of music files I'd ripped on my PC, the speed was very slow as it went via the routers Ethernet ports.  Once I got the switch, and with everything plugged into that, the speeds were ten times faster when transferring files.

Davinadavis posted:

Thank you everyone. I know it sounds crazy, but in my Mac's 'Network Preferences' there was a box called "Renew DHCP Lease". I ticked that, and system is behaving it self at the moment. No idea if that sorted it??

Renew DHCP lease just means that the device on which you are looking at this option asks the router for a new "lease", ie an IP address and the related DNS and network mask IP numbers.  The router has a length of lease setting which is probably somewhere between a day and a week but will be whatever is set in the router.  When a lease expires, it is usually renewed automatically for the same period again and is completely transparent to the user. So by manually renewing it, you just start a new lease period immediately. This facility can be useful if you move between networks a lot and occasionally find that your Mac hasn't recognised the new one.

It shouldn't have any effect in practice in the situation you describe, but if something has become corrupted or somehow you have ended up with an IP address which is already in use on the network, then renewing the lease might tidy things up.

best

David

Thank you JOTA...Yes my switch is a Netgear gigabit type. I have spoken at length with Sky, who were very helpful. They told me that I am receiving 22mbps on a non fibre line, which I'm told is damn good. He also told me that there has been no outage or drop for over 6 weeks, which I believe because my Wi-Fi throughout the house is excellent. It is only the Ethernet connection between the Mac and the switch.

As I mentioned previously, I have renewed the DHCP licence in the Mac 'Network Settings', and since then my system has been perfect. Is this a pure coincidence, or have I cracked it?! If you take my Naim system out of the equation, I was unable to access the Internet on the Mac, so I believe the problem was/is at the Mac end.

Thank you David...You posted after I had just replied to JOTA . 

What at you say does make sense. I just find it strange that Wi-Fi is perfect, it's just the Ethernet connection which was/is the problem. The Guy as Sky suggested that the Ethernet cable had broken. It is a 15 metre Audioquest Cable, so not a £5.99 job! Of course, even decent cable can be faulty! 

Actually it makes no sense at all.... your Mac is simply one of the devices on the network and it receives exactly the same 'stream' of data as all others.
In other words - if one piece of equipment does not work it should not really be affecting the others if the connection sequence is as per Mike's image.

Anyhow - glad to hear it works.

For the future reference - the best things to do, if the connection fails:

• Re-boot your modem first
• If the problem persists, re-boot the router (if you run a separate one) and possibly a switch (should not really need re-booting in a domestic environment)
• Re-start all your network devices or get them to re-new their DHCP leases

I also suggest (since you are a Mac user) that you install an AirportExpress (or higher) as your wireless router and as a 'start' of your network. It's one of the most stable routers at the moment.

Davina60 posted:

Ethernet from iMac to router, Ethernet from router to switch, Ethernet from switch to ND5 XS.

I am not convinced on this connection scheme, , OK it might have worked,  but its not logical

The data stream from Mac to ND5 is via the Sky router (probably a bit dodgy with heavy traffic switching abilities) then to another switch & then to the ND5.   I really do not understand why do it this way,  its via two switches,  its simply not logical. 

My schematic is the normally accepted only way for a basic simple audio net ............  

..............  the data stream is Mac to switch to ND5 ...........  the router to switch provides the downlink link for iRadio, Tidal etc & up/down links ND5 to router & via wireless to your control point.  

(What is the proper switch make & model)

Exactly - it's illogical, when straming comes into play.

Adam Zielinski posted:

Actually it makes no sense at all.... your Mac is simply one of the devices on the network and it receives exactly the same 'stream' of data as all others.
In other words - if one piece of equipment does not work it should not really be affecting the others if the connection sequence is as per Mike's image.

 

Actually devices definitely do not receive the same stream of data as all others on a switched network... - and so excluding special broadcast frames - the devices only receive the data with their specific MAC address. The switching function will use ARP to establish which device is reponsing to which address and store it in the switch or bridge MAC address table and ARP cache.

Now if the Mac was not renewing its lease - it might have thought it had an IP address - but the router and its switch might have had different ideas - especially if the MAC address / ARP cache table hadn't been recently flushed - and so the address might have been reassigned - although a correctly functioning DHCP server wouldn't do this if something was already responding with that IP (layer 3)  address assuming the switches were ARPing correctly - which I suspect perhaps they were not.

Therefore it looks like the switch MAC tables and ARP cache on the router / switch might have got them selves in a pickle. Now the wifi link would locally refresh the ARP cache / MAC table on the router wifi bridge and so I can see that working fine - but if the MAC tables on the router and switch have got themselves in a pickle and a corrupt state - it may be the layer 2 switch path never gets restablsihed.

I suspect if the OP powered down everything together and waited a little while and brought back up - it would have started working.... and if not it tends to put to an issue with the Mac PC and its ARP handling. I do assume different IP addresses were used on the Mac PC for both wifi and Ethernet? otherwise other issues could ensue.

So unusual - even unlucky - but not illogical

Interesting to see if enabling lease renew fixes it -

Simon

Hi Mike, I correct myself.

The set up is...Mac to switch - router to switch - ND5 to switch.

All connections are with Audioquest Ethernet cables. The switch is a Netgear 8 port Gigabit. (GS208)

So far, renewing the lease has done the job (touch wood).

Would a dodgy ethernet cable or connector cause a similar issue?

it could - if it was intermittent - but then applying the lease renew is very unlikely to have made a difference in that scenario

S

Davina60 posted:

Hi Mike, I correct myself.

The set up is...Mac to switch - router to switch - ND5 to switch.

So far, renewing the lease has done the job (touch wood).

OK  Great  ..............  I would say fingers crossed,  but as you DID have the ethernet connected with the switch as the central hub (all along) plus the power cycling (lease renew) then crossed fingers are not required  ............  

Thank you Mike.

Davina

Out of interest, can you folks tell me why you still have separate modem, routers and switches? Sounds rather quaint to me.  Aren't you just increasing the likelihood of a connection failure somewhere?

My Homehub5 is a modem/router combined and has 4 GigE connections and works perfectly unless Openreach dig up the road.  Isn't one box a damn sight easier, more elegant and less prone to error than three?  What am I missing here?