Your ISP's DHCP does not function correctly

[elrengo]

Have you Googled "Your ISP's DHCP does not function correctly"?

OE

Yes with out notice. As I say before the issue is in Asus Device. not in Cablemodem

 

[ricky124]

I just solved this issue by unplugging the modem for about 30 seconds, and then waiting a few minutes so it's fully up and running. I then plugged in my router and it came up connected. I believe someone in the thread that the router boots up quicker than the modem, and even though the modem appears to be ready, in my case "with all green lights" but in reality the modem was not completely up and running. I hope this helps.

 

[danioj]

Good Morning All,

Frequent visitor, infrequent poster, so I'll start with a big THANK YOU to all those who help me through their posts and don't know it. I hope you're all staying safe throughout this current worldwide pandemic.

I thought I would log on and share my experience and ultimate fix to the "Your ISP's DHCP did not function correctly" which I originally diagnosed as being the random "Internet Disconnected" problem as well as "Max number of concurrent DNS queries reached".

Firstly, I will say, that I update the modem regularly and following the update do a hard reboot. Thats it for maintenance.

My internet service is Cable provided by Optus in Australia and the modem I have is a CM500V-1STAUS running V101.08 (not latest) FW. Its just a dumb modem with no routing capabilities (e.g. not an all in one) so no need to run it in bridge mode.

My router is a Asus RT-AC88U bought retail in Australia and has been flashed with latest (pretty much always) Asuswrt-Merlin FW since day 1. Currently V384.16 (was V384.14 when I started noticing the issues).

I run a setup which includes:

- Static IP's to ALL clients
- OpenVPN Client (setup to provide connection through the VPN to only certain IP's while connected and no connection if the VPN is down)
- Side by side Wireless bands (2G and 5G)
- All of the features enabled as per the available functionality and the security scan (except 1 port forward)
- Adaptive QoS for media streaming
- Even mix of fixed and wireless clients
- Network is full of mix of clients from Android, Apple, IoT, work laptops, Google devices etc.

Other than the above, I pretty much run default settings.

Very straight forward. It had run great (or I had not realised issues) for many years until recently. Much like many people, working from home due to COVID-19 I was beginning to rely on the router much more than I ever had. It is over the past couple of weeks that I had noticed those "issues". I out the issues in quotes as I have a feeling that they some could have been a symptom of the other or even my approach to maintenance. I didn't feel like it had anything to do with my use of the functionality of the router.

I tried all the "fixes" and nothing worked. The only thing that seemed to work was a reboot of the router which I was doing at an increasing rate (12 times in an 8 hour period at one point). Then I came upon some advice that seemed to crop up from time to time suggesting a flash of the router to the FW I wanted to run and then a factory reset. Urgh. I did NOT want to do that. So time consuming. So annoying. So many settings to have to write down and then re input (most advice I read advised against restoring settings from a backup).

So, I persisted stubbornly through the last week (pregnant primary school teacher GF working from home and not very happy with apparent unstable connection especially when trying to run Zoom and Webex sessions with kids) of continuous intermittent internet connection, router reboots and things being thrown at me when internet drops at the worst possible moment (not much of an issue for me as I run off a seperate Telstra dongle for work).

Yesterday was the last straw. I bit the bullet. Noted down all my key settings, updated to the latest FW and did a factory reset. Re input my static IP table, input VPN settings (and assigned those IPS to the access table), sorted wireless settings (decided to go with new and slightly different access point names so I could also investigate if any client was causing issues), enabled all router features and truly earned my beer.

The result? Everything is perfect again. It has been running since 7pm last night (it is now 8:29am) without a drop in connection or any one of those "issues" being noted in the log. In fact the log is almost quiet, filled only with a log of the hourly renewal of the VPN TLS key. If it wasn't for that, the log would be all but empty.

I know it might not be what some want to hear (or read as it is) but doing a reset (especially if you have been running for a long time after many FW upgrades) might just be your answer. It is a ball ache but you can help yourself by noting your settings beforehand so you can input faster. I think all the time I spent troubleshooting and trying to avoid a reset, I could have done a reset 4 times over.

Now I am sat here, on my day off (like many businesses mine has asked if we would take some AL while we are in this current pandemic - so I am on a 4 day week till end of June), with a happy GF working in her office on a stable connection with nothing for me to do today but startup up the pellet smoker and smoke some beef ribs while chugging a few (or maybe several) beers.

To quote Albus Dumbledore I hope someone finds this post "entertaining and instructive" if not just generally helpful.

Stay safe and stay indoors.

 

[OzarkEdge]

Good Morning All,

Frequent visitor, infrequent poster, so I'll start with a big THANK YOU to all those who help me through their posts and don't know it. I hope you're all staying safe throughout this current worldwide pandemic.

I thought I would log on and share my experience and ultimate fix to the "Your ISP's DHCP did not function correctly" which I originally diagnosed as being the random "Internet Disconnected" problem as well as "Max number of concurrent DNS queries reached".

Firstly, I will say, that I update the modem regularly and following the update do a hard reboot. Thats it for maintenance.

My internet service is Cable provided by Optus in Australia and the modem I have is a CM500V-1STAUS running V101.08 (not latest) FW. Its just a dumb modem with no routing capabilities (e.g. not an all in one) so no need to run it in bridge mode.

My router is a Asus RT-AC88U bought retail in Australia and has been flashed with latest (pretty much always) Asuswrt-Merlin FW since day 1. Currently V384.16 (was V384.14 when I started noticing the issues).

I run a setup which includes:

- Static IP's to ALL clients
- OpenVPN Client (setup to provide connection through the VPN to only certain IP's while connected and no connection if the VPN is down)
- Side by side Wireless bands (2G and 5G)
- All of the features enabled as per the available functionality and the security scan (except 1 port forward)
- Adaptive QoS for media streaming
- Even mix of fixed and wireless clients
- Network is full of mix of clients from Android, Apple, IoT, work laptops, Google devices etc.

Other than the above, I pretty much run default settings.

Very straight forward. It had run great (or I had not realised issues) for many years until recently. Much like many people, working from home due to COVID-19 I was beginning to rely on the router much more than I ever had. It is over the past couple of weeks that I had noticed those "issues". I out the issues in quotes as I have a feeling that they some could have been a symptom of the other or even my approach to maintenance. I didn't feel like it had anything to do with my use of the functionality of the router.

I tried all the "fixes" and nothing worked. The only thing that seemed to work was a reboot of the router which I was doing at an increasing rate (12 times in an 8 hour period at one point). Then I came upon some advice that seemed to crop up from time to time suggesting a flash of the router to the FW I wanted to run and then a factory reset. Urgh. I did NOT want to do that. So time consuming. So annoying. So many settings to have to write down and then re input (most advice I read advised against restoring settings from a backup).

So, I persisted stubbornly through the last week (pregnant primary school teacher GF working from home and not very happy with apparent unstable connection especially when trying to run Zoom and Webex sessions with kids) of continuous intermittent internet connection, router reboots and things being thrown at me when internet drops at the worst possible moment (not much of an issue for me as I run off a seperate Telstra dongle for work).

Yesterday was the last straw. I bit the bullet. Noted down all my key settings, updated to the latest FW and did a factory reset. Re input my static IP table, input VPN settings (and assigned those IPS to the access table), sorted wireless settings (decided to go with new and slightly different access point names so I could also investigate if any client was causing issues), enabled all router features and truly earned my beer.

The result? Everything is perfect again. It has been running since 7pm last night (it is now 8:29am) without a drop in connection or any one of those "issues" being noted in the log. In fact the log is almost quiet, filled only with a log of the hourly renewal of the VPN TLS key. If it wasn't for that, the log would be all but empty.

I know it might not be what some want to hear (or read as it is) but doing a reset (especially if you have been running for a long time after many FW upgrades) might just be your answer. It is a ball ache but you can help yourself by noting your settings beforehand so you can input faster. I think all the time I spent troubleshooting and trying to avoid a reset, I could have done a reset 4 times over.

Now I am sat here, on my day off (like many businesses mine has asked if we would take some AL while we are in this current pandemic - so I am on a 4 day week till end of June), with a happy GF working in her office on a stable connection with nothing for me to do today but startup up the pellet smoker and smoke some beef ribs while chugging a few (or maybe several) beers.

To quote Albus Dumbledore I hope someone finds this post "entertaining and instructive" if not just generally helpful.

Stay safe and stay indoors.

About the factory default reset.

Make sure your pregnant GF reads your post to give her some hope for you yet.

Stay well, down under.

OE

 

[cplay]

Good Morning All,

Frequent visitor, infrequent poster, so I'll start with a big THANK YOU to all those who help me through their posts and don't know it. I hope you're all staying safe throughout this current worldwide pandemic.

I thought I would log on and share my experience and ultimate fix to the "Your ISP's DHCP did not function correctly" which I originally diagnosed as being the random "Internet Disconnected" problem as well as "Max number of concurrent DNS queries reached".

Firstly, I will say, that I update the modem regularly and following the update do a hard reboot. Thats it for maintenance.

My internet service is Cable provided by Optus in Australia and the modem I have is a CM500V-1STAUS running V101.08 (not latest) FW. Its just a dumb modem with no routing capabilities (e.g. not an all in one) so no need to run it in bridge mode.

My router is a Asus RT-AC88U bought retail in Australia and has been flashed with latest (pretty much always) Asuswrt-Merlin FW since day 1. Currently V384.16 (was V384.14 when I started noticing the issues).

I run a setup which includes:

- Static IP's to ALL clients
- OpenVPN Client (setup to provide connection through the VPN to only certain IP's while connected and no connection if the VPN is down)
- Side by side Wireless bands (2G and 5G)
- All of the features enabled as per the available functionality and the security scan (except 1 port forward)
- Adaptive QoS for media streaming
- Even mix of fixed and wireless clients
- Network is full of mix of clients from Android, Apple, IoT, work laptops, Google devices etc.

Other than the above, I pretty much run default settings.

Very straight forward. It had run great (or I had not realised issues) for many years until recently. Much like many people, working from home due to COVID-19 I was beginning to rely on the router much more than I ever had. It is over the past couple of weeks that I had noticed those "issues". I out the issues in quotes as I have a feeling that they some could have been a symptom of the other or even my approach to maintenance. I didn't feel like it had anything to do with my use of the functionality of the router.

I tried all the "fixes" and nothing worked. The only thing that seemed to work was a reboot of the router which I was doing at an increasing rate (12 times in an 8 hour period at one point). Then I came upon some advice that seemed to crop up from time to time suggesting a flash of the router to the FW I wanted to run and then a factory reset. Urgh. I did NOT want to do that. So time consuming. So annoying. So many settings to have to write down and then re input (most advice I read advised against restoring settings from a backup).

So, I persisted stubbornly through the last week (pregnant primary school teacher GF working from home and not very happy with apparent unstable connection especially when trying to run Zoom and Webex sessions with kids) of continuous intermittent internet connection, router reboots and things being thrown at me when internet drops at the worst possible moment (not much of an issue for me as I run off a seperate Telstra dongle for work).

Yesterday was the last straw. I bit the bullet. Noted down all my key settings, updated to the latest FW and did a factory reset. Re input my static IP table, input VPN settings (and assigned those IPS to the access table), sorted wireless settings (decided to go with new and slightly different access point names so I could also investigate if any client was causing issues), enabled all router features and truly earned my beer.

The result? Everything is perfect again. It has been running since 7pm last night (it is now 8:29am) without a drop in connection or any one of those "issues" being noted in the log. In fact the log is almost quiet, filled only with a log of the hourly renewal of the VPN TLS key. If it wasn't for that, the log would be all but empty.

I know it might not be what some want to hear (or read as it is) but doing a reset (especially if you have been running for a long time after many FW upgrades) might just be your answer. It is a ball ache but you can help yourself by noting your settings beforehand so you can input faster. I think all the time I spent troubleshooting and trying to avoid a reset, I could have done a reset 4 times over.

Now I am sat here, on my day off (like many businesses mine has asked if we would take some AL while we are in this current pandemic - so I am on a 4 day week till end of June), with a happy GF working in her office on a stable connection with nothing for me to do today but startup up the pellet smoker and smoke some beef ribs while chugging a few (or maybe several) beers.

To quote Albus Dumbledore I hope someone finds this post "entertaining and instructive" if not just generally helpful.

Stay safe and stay indoors.

It's great that works for you currently however there are many, many people who have followed your steps with no luck.

This issue is actually dhcp issue that will be fixed in upcoming firmware versions whereby a "continuous" dhcp mode in addition to the existing normal and aggressive dhcp query frequency modes currently.

In fact, on this thread Jack from ASUS is actually sending people beta, test firmware with this feature to help ease the suffering and get feedback:
https://forums.whirlpool.net.au/archive/2719867

Also, thread on DHCP issue that explains coming fix is here:
https://www.snbforums.com/threads/a...or-isps-dhcp-did-not-function-properly.61907/

You shouldn't have to be factory resetting routers after every firmware upgrade or if there are any issues. @RMerlin "dirty" upgrades every single time without issue and specifically mentions in firmware if factory resets are needed.

But yeah, congrats on your fix, this issue is a right pain in the arse.

 

[solstyce]

Just in case anyone on this thread is suffering from the same problem I was - there is a problem with Asus' Adaptive QoS. One of their iptables rules blocks DHCP renewal, at least it does for me and my Pace 5268ac gateway. This results in your WAN going down every time your DHCP lease expires. This was very obvious for ATT since they have a 10 minute lease. If you lease is longer, it may be less obvious.

You can fix it by opening a hole in iptables for DHCP to your gateway.

Thread here.

 

[mguzman011]

Hi, just adding to this thread since I'd been having this issue for a few months. Tried basically all of the fixes posted here (even a different ASUS router, and factory resetting everything SEVERAL times), but there was no consistent fix until I just called my provider (Spectrum) and they sent someone out to my area to look at it. When the technician checked it out, they replaced some wires that were seriously worn down and old. It's been about two weeks now, and I've only had one outage since then due to some storms in my area.

A good way to check if this might be an issue you're having is to connect to your modem directly and see what your downlink/uplink signals are. I don't remember the exact values off the top of my head that you should be getting, but a search on some other forums might be good. In my case, when I called Spectrum to try to get someone here, a few of the uplink channels weren't even showing ANY signal, so they just immediately said "yeah that's your problem".

Edit: I will say, the most consistent thing to fix it before I called them was to unplug router and modem, then plug in ONLY the modem and let it boot for a few mins, then plug in the router. There were plenty of times where this didn't work, but it was the most consistent.

 

[trevorklat]

@danioj
The only thing that worked for me was upgrading to the latest firmware and then doing a factory default reset. With over 40 devices in the DHCP manual reservation table, it was painful. (I wish there was a reliable means of capturing just this data and then being able to reload just this data.) However, after redoing my AiMesh, five wireless network SSIDs, and my port-forwarding/DDNS, I must say it cured my dropped connections and my "Your ISP's DHCP does not function correctly" problems.

Note: I called Xfinity (my ISP) and had them check my signal and modem prior to doing this so that I could rule that out first. (Here in Texas heat, my cable in the backyard wears out every few years and the MOCA splitter/amplifiers tend to die every so often in the hot attic.)

My router (RT-AC5300) and its AiMesh companion (RT-AC86U) had both been upgraded with two for more firmware via the "dirty" method. I did a factory default reset on the AC86U and then swapped it into the AC5300's place. I immediately noticed that everything worked again. This led me to believe that the "dirty" upgrades finally became a problem. Now, with both undergoing factory default resets, everything works again.

 

[distilled]

@danioj
The only thing that worked for me was upgrading to the latest firmware and then doing a factory default reset. With over 40 devices in the DHCP manual reservation table, it was painful. (I wish there was a reliable means of capturing just this data and then being able to reload just this data.)

Could you do a factory reset on the router, then before changing anything else significant, set up the DHCP reservations and then do a backup? It isn't really the same as an independent backup of the reservations, but it would be the closest thing. I would love this too, having > 40 devices on one of the LANs, and because I upload a little picture for each different gadget. It is an unexciting way to spend an hour.

 

[trevorklat]

@distilled

I suppose that would be one way to do it but I don't know if it would load correctly into the new firmware via a restore utility. Note: I gave up on the little custom icons long ago as it was just too time-consuming to reload them after factory resets.

 

[K-2SO]

just too time-consuming to reload them after factory resets.

A user here on SNB posted the following save/restore commands (ASUS is the USB drive):
(unfortunately, I can't find the source to give credit to the right person)

Save:

nvram get dhcp_staticlist > /tmp/mnt/ASUS/backup/dhcplist.txt
nvram get custom_clientlist > /tmp/mnt/ASUS/backup/custom_clientlist.txt

cp /jffs/nvram/dhcp_hostnames /tmp/mnt/ASUS/backup/jfssnvram_dhcp_hostnames.txt
cp -r /jffs/usericon /tmp/mnt/ASUS/backup/

Restore:

cd /mnt/ASUS
nvram set dhcp_staticlist="`cat /tmp/mnt/ASUS/backup/dhcplist.txt`"
nvram set custom_clientlist="`cat /tmp/mnt/ASUS/backup/custom_clientlist.txt`"

cp /tmp/mnt/ASUS/backup/jfssnvram_dhcp_hostnames.txt /jffs/nvram/dhcp_hostnames
cp -r /tmp/mnt/ASUS/backup/usericon /jffs/

nvram commit && reboot

I would like someone like @ColinTaylor to look at the above and confirm what it does. I see it creates a folder /backup with the extracted data, then restores the files to corresponding places. I never used it though and I'm not very familiar with jffs contents. Not sure if it works on different routers either.

 

[distilled]

I literally can't give them up. It is probably an OCD trait. If certain things are there, I "have" to use them, or things look incomplete. It's a sickness, mate. On the upside, it does look cool.

 

[ColinTaylor]

A user here on SNB posted the following save/restore commands (ASUS is the USB drive):
(unfortunately, I can't find the source to give credit to the right person)

Save:

nvram get dhcp_staticlist > /tmp/mnt/ASUS/backup/dhcplist.txt
nvram get custom_clientlist > /tmp/mnt/ASUS/backup/custom_clientlist.txt

cp /jffs/nvram/dhcp_hostnames /tmp/mnt/ASUS/backup/jfssnvram_dhcp_hostnames.txt
cp -r /jffs/usericon /tmp/mnt/ASUS/backup/

Restore:

cd /mnt/ASUS
nvram set dhcp_staticlist="`cat /tmp/mnt/ASUS/backup/dhcplist.txt`"
nvram set custom_clientlist="`cat /tmp/mnt/ASUS/backup/custom_clientlist.txt`"

cp /tmp/mnt/ASUS/backup/jfssnvram_dhcp_hostnames.txt /jffs/nvram/dhcp_hostnames
cp -r /tmp/mnt/ASUS/backup/usericon /jffs/

nvram commit && reboot

I would like someone like @ColinTaylor to look at the above and confirm what it does. I see it creates a folder /backup with the extracted data, then restores the files to corresponding places. I never used it though and I'm not very familiar with jffs contents. Not sure if it works on different routers either.

Looks like you got those commands from this post.

It assumes that you already have a USB drive attached to the router as /tmp/mnt/ASUS and that contains a directory called backup.

Merlin split the nvram variable that contained the manual DHCP assignments into two, dhcp_staticlist and dhcp_hostnames. Even though the latter is now stored in /jffs/nvram for HND routers personally I'd still use the nvram interface to read and write to it. NOTE: I don't have an HND router so I can't check the command for dhcp_hostnames works so you'll need to verify that for you own router.

custom_clientlist contains the "Clients Names", not to be confused with host names.

/jffs/usericon is a directory that contains the user icons. Duh!

Using `` in a script is depreciated in favour of $(...) so I'd do:

nvram get dhcp_staticlist > /tmp/mnt/ASUS/backup/dhcp_staticlist.txt
nvram get dhcp_hostnames > /tmp/mnt/ASUS/backup/dhcp_hostnames.txt
nvram get custom_clientlist > /tmp/mnt/ASUS/backup/custom_clientlist.txt

cp -a /jffs/usericon /tmp/mnt/ASUS/backup/

nvram set dhcp_staticlist="$(cat /tmp/mnt/ASUS/backup/dhcp_staticlist.txt)"
nvram set dhcp_hostnames="$(cat /tmp/mnt/ASUS/backup/dhcp_hostnames.txt)"
nvram set custom_clientlist="$(cat /tmp/mnt/ASUS/backup/custom_clientlist.txt)"

cp -a /tmp/mnt/ASUS/backup/usericon /jffs/

nvram commit && reboot

 

[K-2SO]

Looks like you got those commands from this post.

Thank you @LimJK and @ColinTaylor!

I had a copy/paste of it, perhaps the post above is the original source. I don't have a proper router to test, but it may save a lot of time to someone else.

 

[vrapp]

This is caused by the limitation where either the modem, or provider allows only one MAC connected to the modem. It remembers the MAC that connected first, so when you connect another, DHCP does not give out the address and the router shows this message. To fix, you need to either power cycle the modem, or clone MAC that the modem already knows, in router's settings. This explanation is based on this post: https://www.dslreports.com/forum/r32969775- , which so far seems to be the only one that explained what's going on. If powercycling does not work, you need to call provider and ask them to re-provision the modem. In fact they may be able to just erase the stored MAC, but the 1st level rep may be not trained for that.
DHCP frequency, QoS settings, factory reset, flipping IPv6, and 100 other suggestions found on this forum and numerous others, occasionally seem to work, but this is only because the timing of that particular effort coincided with the expiration of the first MAC, which can be anything between 10 minutes and several days.

 

[dlandiss]

This is caused by the limitation where either the modem, or provider allows only one MAC connected to the modem. It remembers the MAC that connected first, so when you connect another, DHCP does not give out the address and the router shows this message.

There must be other reasons. My ASUS RT-AC68 used to chug along happily for weeks with no notifications, and then suddenly flash that error message with no action that would change its address.

 

[vrapp]

There must be other reasons. My ASUS RT-AC68 used to chug along happily for weeks with no notifications, and then suddenly flash that error message with no action that would change its address.

Which means that for whatever reason the provider was now expecting another MAC.