Re: [MT-AU Public] Public Digest, Vol 17, Issue 10
Hey there, It is my experience that anything cable provided is prone to excessive congestion and also IP Address changes at a whim - it is considered to be a residential service after all. Congestion will cause slowness to the internet and that is purely and simply due to the amount of people using the same cable in the street or area. Remember it is just one cable from the pole going to every location in the street or neighbourhood so it is very prone to congested periods no matter what you do at the clients end. In the past, I have copied the Mac of the first device that connects to the Cable Modem and used that in the Router, or I would log into the cable modem and address the advanced settings to resolve the issues of 1 x Mac connection only or get rid of the modem completely if I can and use a better model. Perhaps using Dynamic DNS would assist you in your endeavours if you need to address the Mikrotik Router. Just my 2 cents worth. Regards, Kevin Scott SCOTTS IP Ph: (03) 9008-5696 Fx: (03) 9008-5686 Mb: 0419-650-550 Web: www.scottsip.com.au ---------------------------------------------------------------------------------------------------------------- This communication, including any attachments, is confidential. If you are not the intended recipient, you should not read it - please contact me immediately, destroy it, and do not copy or use any part of this communication or disclose anything about it. ---------------------------------------------------------------------------------------------------------------- On 28/07/2015 12:00 PM, public-request@talk.mikrotik.com.au wrote:
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Today's Topics:
1. Cable Modem DHCP Issues (Ben Jackson) 2. Re: Cable Modem DHCP Issues (Paul Julian)
----------------------------------------------------------------------
Message: 1 Date: Tue, 28 Jul 2015 10:53:10 +1000 From: Ben Jackson <ben@elogik.net> To: MikroTik Australia Public List <public@talk.mikrotik.com.au> Subject: [MT-AU Public] Cable Modem DHCP Issues Message-ID: <CACv=4uox=iLAVoMx_qQ7+if1VPSJ2r9orvvXwzK=wDrjHEjkvA@mail.gmail.com> Content-Type: text/plain; charset=UTF-8
Hi All,
I'm hoping someone can help me as I'm at my wit's end with this one.
We use Mikrotik gear (Mainly RB2011's and and more recently, the CRS125-24G) in large residential AV situations where invariably, the Mikrotik is in dhcp client mode, in a cable internet scenario where Telstra's / Optus's modem has been placed into "bridge" mode (NAT switched off) and the carrier-supplied WAN IP address gets bound to the gateway interface of the Mikrotik.
The Mikrotik, in turn is connected to, on average, about 3 UniFi access points, and at least 3-4 zones of Sonos. On initial set up, everything seems to work great, with the full bandwidth of the cable modem getting passed on to the rest of the network, even when 802.11 clients are connected (a testament to the UniFi's I my opinion - I only use dual band Pro AP's).
However, after a week or so the internet connection seems to get either very slow, or stop working altogether. If I look in the logs (with dhcp logging switched on) I can see regular NAK's getting passed from the dhcp server on the cable modem. The problem is I don't really understand how DHCP works on cable modems. I'm assuming every so often the cable modem gets a new IP address from the carrier (normally after a reset) and at this point the modem is not passing this new address onto the Mikrotik which is effectively cut off from the internet. Since we are stuck with using Bigpond and Optus modems these are the only solutions I have discovered which seem to stop the issue from occurring (at least as regularly).
1) Leave the cable modem in "router" mode and switch off all extraneous services such as Wi-Fi, and also put one IP address in the dhcp pool so that the Mikrotik always gets the same private IP address. However, this creates a double nat situation which means I can no longer perform reliable port forwarding for things such as DVR's and CBus controllers (which I find the Mikrotik's great for).
2) Allow the cable modem to perform all dhcp, routing, port forwarding (which is a joke on these devices) and firewall tasks for the entire LAN and turn the CRS into an unmanaged L2 switch. The main problem here is that these Bigpond devices simply do not have the grunt to deal with large networks with lots of AV streaming and control happening.
Since both of the above have severe drawbacks in terms of functionality, I wonder if anyone has had similar experiences as I am just about ready to dump the MikroTik's and start looking at other options in the hope that they play better with the Bigpond gear.
Thanks in advance,
Ben Jackson eLogik m:0404 924745 e: ben@elogik.net w: www.elogik.com.au [image: http://www.elogik.com.au] <http://www.elogik.com.au>
------------------------------
Message: 2 Date: Tue, 28 Jul 2015 11:11:01 +1000 From: Paul Julian <paul@oxygennetworks.com.au> To: 'MikroTik Australia Public List' <public@talk.mikrotik.com.au> Subject: Re: [MT-AU Public] Cable Modem DHCP Issues Message-ID: <c7a5c37b-7d25-4bbe-9f2e-2ae88ae61963@oxygennetworks.com.au> Content-Type: text/plain; charset="us-ascii"
Hey Ben, the only thing I can think of is that Telstra and Optus Cable networks use MAC based DHCP, they bind the IP to the MAC of the NTU or in the case of bridge mode the first client that makes a request, and often you have trouble with these things because of this, I don't really think it's a Mikrotik thing.
However, as long as the Mikrotik is maintaining the same MAC on the interface plugged into the NTU and the NTU is truly in bridge mode and the Mikrotik is the only thing plugged into the NTU I can't see why it would be having issues.
Is there any chance that another device might somehow be getting a DHCP request through to the NTU somehow the way you have it all plugged in ?
Regards Paul
-----Original Message----- From: Public [mailto:public-bounces@talk.mikrotik.com.au] On Behalf Of Ben Jackson Sent: Tuesday, 28 July 2015 10:53 AM To: MikroTik Australia Public List Subject: [MT-AU Public] Cable Modem DHCP Issues
Hi All,
I'm hoping someone can help me as I'm at my wit's end with this one.
We use Mikrotik gear (Mainly RB2011's and and more recently, the CRS125-24G) in large residential AV situations where invariably, the Mikrotik is in dhcp client mode, in a cable internet scenario where Telstra's / Optus's modem has been placed into "bridge" mode (NAT switched off) and the carrier-supplied WAN IP address gets bound to the gateway interface of the Mikrotik.
The Mikrotik, in turn is connected to, on average, about 3 UniFi access points, and at least 3-4 zones of Sonos. On initial set up, everything seems to work great, with the full bandwidth of the cable modem getting passed on to the rest of the network, even when 802.11 clients are connected (a testament to the UniFi's I my opinion - I only use dual band Pro AP's).
However, after a week or so the internet connection seems to get either very slow, or stop working altogether. If I look in the logs (with dhcp logging switched on) I can see regular NAK's getting passed from the dhcp server on the cable modem. The problem is I don't really understand how DHCP works on cable modems. I'm assuming every so often the cable modem gets a new IP address from the carrier (normally after a reset) and at this point the modem is not passing this new address onto the Mikrotik which is effectively cut off from the internet. Since we are stuck with using Bigpond and Optus modems these are the only solutions I have discovered which seem to stop the issue from occurring (at least as regularly).
1) Leave the cable modem in "router" mode and switch off all extraneous services such as Wi-Fi, and also put one IP address in the dhcp pool so that the Mikrotik always gets the same private IP address. However, this creates a double nat situation which means I can no longer perform reliable port forwarding for things such as DVR's and CBus controllers (which I find the Mikrotik's great for).
2) Allow the cable modem to perform all dhcp, routing, port forwarding (which is a joke on these devices) and firewall tasks for the entire LAN and turn the CRS into an unmanaged L2 switch. The main problem here is that these Bigpond devices simply do not have the grunt to deal with large networks with lots of AV streaming and control happening.
Since both of the above have severe drawbacks in terms of functionality, I wonder if anyone has had similar experiences as I am just about ready to dump the MikroTik's and start looking at other options in the hope that they play better with the Bigpond gear.
Thanks in advance,
Ben Jackson eLogik m:0404 924745 e: ben@elogik.net w: www.elogik.com.au [image: http://www.elogik.com.au] <http://www.elogik.com.au> _______________________________________________ Public mailing list Public@talk.mikrotik.com.au http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com.au
------------------------------
Subject: Digest Footer
_______________________________________________ Public mailing list Public@talk.mikrotik.com.au http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com.au
------------------------------
End of Public Digest, Vol 17, Issue 10 **************************************
Thanks Scott, yes I'm all too aware of the limitations of cable, but I have installed enough of these to get a good feel for what happens in congested periods. There is something weird going on above and beyond the usual congestion. I'm interested in your comment about using a better model - do the ISP's support this? Would you have any suggestions as to what model to use? Thanks Ben Jackson eLogik m:0404 924745 e: ben@elogik.net w: www.elogik.com.au [image: http://www.elogik.com.au] <http://www.elogik.com.au> On Tue, Jul 28, 2015 at 12:27 PM, Kevin Scott <kevin@scottsip.com.au> wrote:
Hey there,
It is my experience that anything cable provided is prone to excessive congestion and also IP Address changes at a whim - it is considered to be a residential service after all.
Congestion will cause slowness to the internet and that is purely and simply due to the amount of people using the same cable in the street or area. Remember it is just one cable from the pole going to every location in the street or neighbourhood so it is very prone to congested periods no matter what you do at the clients end.
In the past, I have copied the Mac of the first device that connects to the Cable Modem and used that in the Router, or I would log into the cable modem and address the advanced settings to resolve the issues of 1 x Mac connection only or get rid of the modem completely if I can and use a better model.
Perhaps using Dynamic DNS would assist you in your endeavours if you need to address the Mikrotik Router.
Just my 2 cents worth.
Regards,
Kevin Scott
SCOTTS IP
Ph: (03) 9008-5696 Fx: (03) 9008-5686 Mb: 0419-650-550
Web: www.scottsip.com.au
---------------------------------------------------------------------------------------------------------------- This communication, including any attachments, is confidential. If you are not the intended recipient, you should not read it - please contact me immediately, destroy it, and do not copy or use any part of this communication or disclose anything about it.
----------------------------------------------------------------------------------------------------------------
On 28/07/2015 12:00 PM, public-request@talk.mikrotik.com.au wrote:
Send Public mailing list submissions to public@talk.mikrotik.com.au
To subscribe or unsubscribe via the World Wide Web, visit
http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com.au
or, via email, send a message with subject or body 'help' to public-request@talk.mikrotik.com.au
You can reach the person managing the list at public-owner@talk.mikrotik.com.au
When replying, please edit your Subject line so it is more specific than "Re: Contents of Public digest..."
Today's Topics:
1. Cable Modem DHCP Issues (Ben Jackson) 2. Re: Cable Modem DHCP Issues (Paul Julian)
----------------------------------------------------------------------
Message: 1 Date: Tue, 28 Jul 2015 10:53:10 +1000 From: Ben Jackson <ben@elogik.net> To: MikroTik Australia Public List <public@talk.mikrotik.com.au> Subject: [MT-AU Public] Cable Modem DHCP Issues Message-ID: <CACv=4uox=iLAVoMx_qQ7+if1VPSJ2r9orvvXwzK= wDrjHEjkvA@mail.gmail.com> Content-Type: text/plain; charset=UTF-8
Hi All,
I'm hoping someone can help me as I'm at my wit's end with this one.
We use Mikrotik gear (Mainly RB2011's and and more recently, the CRS125-24G) in large residential AV situations where invariably, the Mikrotik is in dhcp client mode, in a cable internet scenario where Telstra's / Optus's modem has been placed into "bridge" mode (NAT switched off) and the carrier-supplied WAN IP address gets bound to the gateway interface of the Mikrotik.
The Mikrotik, in turn is connected to, on average, about 3 UniFi access points, and at least 3-4 zones of Sonos. On initial set up, everything seems to work great, with the full bandwidth of the cable modem getting passed on to the rest of the network, even when 802.11 clients are connected (a testament to the UniFi's I my opinion - I only use dual band Pro AP's).
However, after a week or so the internet connection seems to get either very slow, or stop working altogether. If I look in the logs (with dhcp logging switched on) I can see regular NAK's getting passed from the dhcp server on the cable modem. The problem is I don't really understand how DHCP works on cable modems. I'm assuming every so often the cable modem gets a new IP address from the carrier (normally after a reset) and at this point the modem is not passing this new address onto the Mikrotik which is effectively cut off from the internet. Since we are stuck with using Bigpond and Optus modems these are the only solutions I have discovered which seem to stop the issue from occurring (at least as regularly).
1) Leave the cable modem in "router" mode and switch off all extraneous services such as Wi-Fi, and also put one IP address in the dhcp pool so that the Mikrotik always gets the same private IP address. However, this creates a double nat situation which means I can no longer perform reliable port forwarding for things such as DVR's and CBus controllers (which I find the Mikrotik's great for).
2) Allow the cable modem to perform all dhcp, routing, port forwarding (which is a joke on these devices) and firewall tasks for the entire LAN and turn the CRS into an unmanaged L2 switch. The main problem here is that these Bigpond devices simply do not have the grunt to deal with large networks with lots of AV streaming and control happening.
Since both of the above have severe drawbacks in terms of functionality, I wonder if anyone has had similar experiences as I am just about ready to dump the MikroTik's and start looking at other options in the hope that they play better with the Bigpond gear.
Thanks in advance,
Ben Jackson eLogik m:0404 924745 e: ben@elogik.net w: www.elogik.com.au [image: http://www.elogik.com.au] <http://www.elogik.com.au>
------------------------------
Message: 2 Date: Tue, 28 Jul 2015 11:11:01 +1000 From: Paul Julian <paul@oxygennetworks.com.au> To: 'MikroTik Australia Public List' <public@talk.mikrotik.com.au> Subject: Re: [MT-AU Public] Cable Modem DHCP Issues Message-ID: <c7a5c37b-7d25-4bbe-9f2e-2ae88ae61963@oxygennetworks.com.au> Content-Type: text/plain; charset="us-ascii"
Hey Ben, the only thing I can think of is that Telstra and Optus Cable networks use MAC based DHCP, they bind the IP to the MAC of the NTU or in the case of bridge mode the first client that makes a request, and often you have trouble with these things because of this, I don't really think it's a Mikrotik thing.
However, as long as the Mikrotik is maintaining the same MAC on the interface plugged into the NTU and the NTU is truly in bridge mode and the Mikrotik is the only thing plugged into the NTU I can't see why it would be having issues.
Is there any chance that another device might somehow be getting a DHCP request through to the NTU somehow the way you have it all plugged in ?
Regards Paul
-----Original Message----- From: Public [mailto:public-bounces@talk.mikrotik.com.au] On Behalf Of Ben Jackson Sent: Tuesday, 28 July 2015 10:53 AM To: MikroTik Australia Public List Subject: [MT-AU Public] Cable Modem DHCP Issues
Hi All,
I'm hoping someone can help me as I'm at my wit's end with this one.
We use Mikrotik gear (Mainly RB2011's and and more recently, the CRS125-24G) in large residential AV situations where invariably, the Mikrotik is in dhcp client mode, in a cable internet scenario where Telstra's / Optus's modem has been placed into "bridge" mode (NAT switched off) and the carrier-supplied WAN IP address gets bound to the gateway interface of the Mikrotik.
The Mikrotik, in turn is connected to, on average, about 3 UniFi access points, and at least 3-4 zones of Sonos. On initial set up, everything seems to work great, with the full bandwidth of the cable modem getting passed on to the rest of the network, even when 802.11 clients are connected (a testament to the UniFi's I my opinion - I only use dual band Pro AP's).
However, after a week or so the internet connection seems to get either very slow, or stop working altogether. If I look in the logs (with dhcp logging switched on) I can see regular NAK's getting passed from the dhcp server on the cable modem. The problem is I don't really understand how DHCP works on cable modems. I'm assuming every so often the cable modem gets a new IP address from the carrier (normally after a reset) and at this point the modem is not passing this new address onto the Mikrotik which is effectively cut off from the internet. Since we are stuck with using Bigpond and Optus modems these are the only solutions I have discovered which seem to stop the issue from occurring (at least as regularly).
1) Leave the cable modem in "router" mode and switch off all extraneous services such as Wi-Fi, and also put one IP address in the dhcp pool so that the Mikrotik always gets the same private IP address. However, this creates a double nat situation which means I can no longer perform reliable port forwarding for things such as DVR's and CBus controllers (which I find the Mikrotik's great for).
2) Allow the cable modem to perform all dhcp, routing, port forwarding (which is a joke on these devices) and firewall tasks for the entire LAN and turn the CRS into an unmanaged L2 switch. The main problem here is that these Bigpond devices simply do not have the grunt to deal with large networks with lots of AV streaming and control happening.
Since both of the above have severe drawbacks in terms of functionality, I wonder if anyone has had similar experiences as I am just about ready to dump the MikroTik's and start looking at other options in the hope that they play better with the Bigpond gear.
Thanks in advance,
Ben Jackson eLogik m:0404 924745 e: ben@elogik.net w: www.elogik.com.au [image: http://www.elogik.com.au] <http://www.elogik.com.au> _______________________________________________ Public mailing list Public@talk.mikrotik.com.au http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com.au
------------------------------
Subject: Digest Footer
_______________________________________________ Public mailing list Public@talk.mikrotik.com.au http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com.au
------------------------------
End of Public Digest, Vol 17, Issue 10 **************************************
_______________________________________________ Public mailing list Public@talk.mikrotik.com.au http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com.au
Sorry just noticed your name is Kevin - not Scott - apologies! Ben Jackson eLogik m:0404 924745 e: ben@elogik.net w: www.elogik.com.au [image: http://www.elogik.com.au] <http://www.elogik.com.au> On Tue, Jul 28, 2015 at 12:52 PM, Ben Jackson <ben@elogik.net> wrote:
Thanks Scott, yes I'm all too aware of the limitations of cable, but I have installed enough of these to get a good feel for what happens in congested periods.
There is something weird going on above and beyond the usual congestion.
I'm interested in your comment about using a better model - do the ISP's support this? Would you have any suggestions as to what model to use?
Thanks
Ben Jackson eLogik m:0404 924745 e: ben@elogik.net w: www.elogik.com.au [image: http://www.elogik.com.au] <http://www.elogik.com.au>
On Tue, Jul 28, 2015 at 12:27 PM, Kevin Scott <kevin@scottsip.com.au> wrote:
Hey there,
It is my experience that anything cable provided is prone to excessive congestion and also IP Address changes at a whim - it is considered to be a residential service after all.
Congestion will cause slowness to the internet and that is purely and simply due to the amount of people using the same cable in the street or area. Remember it is just one cable from the pole going to every location in the street or neighbourhood so it is very prone to congested periods no matter what you do at the clients end.
In the past, I have copied the Mac of the first device that connects to the Cable Modem and used that in the Router, or I would log into the cable modem and address the advanced settings to resolve the issues of 1 x Mac connection only or get rid of the modem completely if I can and use a better model.
Perhaps using Dynamic DNS would assist you in your endeavours if you need to address the Mikrotik Router.
Just my 2 cents worth.
Regards,
Kevin Scott
SCOTTS IP
Ph: (03) 9008-5696 Fx: (03) 9008-5686 Mb: 0419-650-550
Web: www.scottsip.com.au
---------------------------------------------------------------------------------------------------------------- This communication, including any attachments, is confidential. If you are not the intended recipient, you should not read it - please contact me immediately, destroy it, and do not copy or use any part of this communication or disclose anything about it.
----------------------------------------------------------------------------------------------------------------
On 28/07/2015 12:00 PM, public-request@talk.mikrotik.com.au wrote:
Send Public mailing list submissions to public@talk.mikrotik.com.au
To subscribe or unsubscribe via the World Wide Web, visit
http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com.au
or, via email, send a message with subject or body 'help' to public-request@talk.mikrotik.com.au
You can reach the person managing the list at public-owner@talk.mikrotik.com.au
When replying, please edit your Subject line so it is more specific than "Re: Contents of Public digest..."
Today's Topics:
1. Cable Modem DHCP Issues (Ben Jackson) 2. Re: Cable Modem DHCP Issues (Paul Julian)
----------------------------------------------------------------------
Message: 1 Date: Tue, 28 Jul 2015 10:53:10 +1000 From: Ben Jackson <ben@elogik.net> To: MikroTik Australia Public List <public@talk.mikrotik.com.au> Subject: [MT-AU Public] Cable Modem DHCP Issues Message-ID: <CACv=4uox=iLAVoMx_qQ7+if1VPSJ2r9orvvXwzK= wDrjHEjkvA@mail.gmail.com> Content-Type: text/plain; charset=UTF-8
Hi All,
I'm hoping someone can help me as I'm at my wit's end with this one.
We use Mikrotik gear (Mainly RB2011's and and more recently, the CRS125-24G) in large residential AV situations where invariably, the Mikrotik is in dhcp client mode, in a cable internet scenario where Telstra's / Optus's modem has been placed into "bridge" mode (NAT switched off) and the carrier-supplied WAN IP address gets bound to the gateway interface of the Mikrotik.
The Mikrotik, in turn is connected to, on average, about 3 UniFi access points, and at least 3-4 zones of Sonos. On initial set up, everything seems to work great, with the full bandwidth of the cable modem getting passed on to the rest of the network, even when 802.11 clients are connected (a testament to the UniFi's I my opinion - I only use dual band Pro AP's).
However, after a week or so the internet connection seems to get either very slow, or stop working altogether. If I look in the logs (with dhcp logging switched on) I can see regular NAK's getting passed from the dhcp server on the cable modem. The problem is I don't really understand how DHCP works on cable modems. I'm assuming every so often the cable modem gets a new IP address from the carrier (normally after a reset) and at this point the modem is not passing this new address onto the Mikrotik which is effectively cut off from the internet. Since we are stuck with using Bigpond and Optus modems these are the only solutions I have discovered which seem to stop the issue from occurring (at least as regularly).
1) Leave the cable modem in "router" mode and switch off all extraneous services such as Wi-Fi, and also put one IP address in the dhcp pool so that the Mikrotik always gets the same private IP address. However, this creates a double nat situation which means I can no longer perform reliable port forwarding for things such as DVR's and CBus controllers (which I find the Mikrotik's great for).
2) Allow the cable modem to perform all dhcp, routing, port forwarding (which is a joke on these devices) and firewall tasks for the entire LAN and turn the CRS into an unmanaged L2 switch. The main problem here is that these Bigpond devices simply do not have the grunt to deal with large networks with lots of AV streaming and control happening.
Since both of the above have severe drawbacks in terms of functionality, I wonder if anyone has had similar experiences as I am just about ready to dump the MikroTik's and start looking at other options in the hope that they play better with the Bigpond gear.
Thanks in advance,
Ben Jackson eLogik m:0404 924745 e: ben@elogik.net w: www.elogik.com.au [image: http://www.elogik.com.au] <http://www.elogik.com.au>
------------------------------
Message: 2 Date: Tue, 28 Jul 2015 11:11:01 +1000 From: Paul Julian <paul@oxygennetworks.com.au> To: 'MikroTik Australia Public List' <public@talk.mikrotik.com.au> Subject: Re: [MT-AU Public] Cable Modem DHCP Issues Message-ID: <c7a5c37b-7d25-4bbe-9f2e-2ae88ae61963@oxygennetworks.com.au> Content-Type: text/plain; charset="us-ascii"
Hey Ben, the only thing I can think of is that Telstra and Optus Cable networks use MAC based DHCP, they bind the IP to the MAC of the NTU or in the case of bridge mode the first client that makes a request, and often you have trouble with these things because of this, I don't really think it's a Mikrotik thing.
However, as long as the Mikrotik is maintaining the same MAC on the interface plugged into the NTU and the NTU is truly in bridge mode and the Mikrotik is the only thing plugged into the NTU I can't see why it would be having issues.
Is there any chance that another device might somehow be getting a DHCP request through to the NTU somehow the way you have it all plugged in ?
Regards Paul
-----Original Message----- From: Public [mailto:public-bounces@talk.mikrotik.com.au] On Behalf Of Ben Jackson Sent: Tuesday, 28 July 2015 10:53 AM To: MikroTik Australia Public List Subject: [MT-AU Public] Cable Modem DHCP Issues
Hi All,
I'm hoping someone can help me as I'm at my wit's end with this one.
We use Mikrotik gear (Mainly RB2011's and and more recently, the CRS125-24G) in large residential AV situations where invariably, the Mikrotik is in dhcp client mode, in a cable internet scenario where Telstra's / Optus's modem has been placed into "bridge" mode (NAT switched off) and the carrier-supplied WAN IP address gets bound to the gateway interface of the Mikrotik.
The Mikrotik, in turn is connected to, on average, about 3 UniFi access points, and at least 3-4 zones of Sonos. On initial set up, everything seems to work great, with the full bandwidth of the cable modem getting passed on to the rest of the network, even when 802.11 clients are connected (a testament to the UniFi's I my opinion - I only use dual band Pro AP's).
However, after a week or so the internet connection seems to get either very slow, or stop working altogether. If I look in the logs (with dhcp logging switched on) I can see regular NAK's getting passed from the dhcp server on the cable modem. The problem is I don't really understand how DHCP works on cable modems. I'm assuming every so often the cable modem gets a new IP address from the carrier (normally after a reset) and at this point the modem is not passing this new address onto the Mikrotik which is effectively cut off from the internet. Since we are stuck with using Bigpond and Optus modems these are the only solutions I have discovered which seem to stop the issue from occurring (at least as regularly).
1) Leave the cable modem in "router" mode and switch off all extraneous services such as Wi-Fi, and also put one IP address in the dhcp pool so that the Mikrotik always gets the same private IP address. However, this creates a double nat situation which means I can no longer perform reliable port forwarding for things such as DVR's and CBus controllers (which I find the Mikrotik's great for).
2) Allow the cable modem to perform all dhcp, routing, port forwarding (which is a joke on these devices) and firewall tasks for the entire LAN and turn the CRS into an unmanaged L2 switch. The main problem here is that these Bigpond devices simply do not have the grunt to deal with large networks with lots of AV streaming and control happening.
Since both of the above have severe drawbacks in terms of functionality, I wonder if anyone has had similar experiences as I am just about ready to dump the MikroTik's and start looking at other options in the hope that they play better with the Bigpond gear.
Thanks in advance,
Ben Jackson eLogik m:0404 924745 e: ben@elogik.net w: www.elogik.com.au [image: http://www.elogik.com.au] <http://www.elogik.com.au> _______________________________________________ Public mailing list Public@talk.mikrotik.com.au http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com.au
------------------------------
Subject: Digest Footer
_______________________________________________ Public mailing list Public@talk.mikrotik.com.au http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com.au
------------------------------
End of Public Digest, Vol 17, Issue 10 **************************************
_______________________________________________ Public mailing list Public@talk.mikrotik.com.au http://talk.mikrotik.com.au/mailman/listinfo/public_talk.mikrotik.com.au
participants (2)
-
Ben Jackson -
Kevin Scott