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New Member
Posts: 27
Registered: ‎12-21-2017
Kudos: 4

Re: 3.9.15.8011 blocks DHCP

This has gone on long enough for us all.

 

If you are affected by this - please log a curt ticket referencing this forum post specifically and ask for an ETA.

 

If we can't get a response from anyone here - we will have to go to them.

New Member
Posts: 7
Registered: ‎05-12-2017
Kudos: 2

Re: 3.9.15.8011 blocks DHCP

New Member
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Registered: ‎09-20-2017
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Re: 3.9.15.8011 blocks DHCP

Upgrading

 

AP's to 3.9.24.8264
Switches to 3.9.21.8191

USG to 4.4.18.5052168

 

have solved the problem for me.

New Member
Posts: 17
Registered: ‎05-06-2014
Kudos: 15

Re: 3.9.15.8011 blocks DHCP

We are still having the problem with 3.9.27, so I don't honestly think the problem is fixed in the latest firmware. I'm rolling back v3.9.6 right now.

New Member
Posts: 16
Registered: ‎09-06-2016

Re: 3.9.15.8011 blocks DHCP

After a long time I upgraded to 3.9.27

I disabled the dhcp snooping for the whole site. DHCP is working fine. But I am now facing issues with HomeKit devices, that are now reported as not responding. I am also rolling back to 3.9.6

 

I bought this stuff to have a stable network, but the firmware messes all that up.

New Member
Posts: 6
Registered: ‎02-14-2017
Kudos: 2

Re: 3.9.15.8011 blocks DHCP

I am expereincg this same issue, do we know if a solution other thatn rolling back the firmware exists yet?

New Member
Posts: 15
Registered: ‎05-14-2016
Kudos: 3

Re: 3.9.15.8011 blocks DHCP

You should complain to Ubiquiti support or use another product. As you can see, this thread is ignored.

New Member
Posts: 27
Registered: ‎12-21-2017
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Re: 3.9.15.8011 blocks DHCP

Ubnt (feel free to prove me wrong @UBNT-MikeD & @UBNT-cid) do not care about firmware bugs or issues reported either here or via support.

Your only option if you can't live with bugs or old firmware is to change hardware.

Vote with your feet - stop buying unsupported, untested and unreliable hardware.

New Member
Posts: 15
Registered: ‎05-14-2016
Kudos: 3

Re: 3.9.15.8011 blocks DHCP

You have a great point. Old firmware works fine for me.
New Member
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Re: 3.9.15.8011 blocks DHCP

[ Edited ]

I discovered that in my system if I stopped all multicast and broadcast traffic on my network this dhcp issue would go away.  For some reason multicast or broadcast traffic on any vlan would block dhcp across all vlans.  I still rolled back the firmware on my switches though as permanently disableing multicast and broadcast traffic on my system is not an option.

New Member
Posts: 27
Registered: ‎12-21-2017
Kudos: 4

Re: 3.9.15.8011 blocks DHCP

That's really interesting @shpoellet!

We are heavy multicast users, it could well be the cause of the issue.

New Member
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Re: 3.9.15.8011 blocks DHCP

If you disable DHCP snooping on the entire site, you do not need to roll back. 

New Member
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Registered: ‎05-14-2016
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Re: 3.9.15.8011 blocks DHCP

[ Edited ]

You're not wrong.

 

But don't underestimate how much time this problem costs. The first few folks who had this issue wasted a lot more time than someone who quickly arrived to this page and found a solution. It's going to happen again and again.

 

I'm not even going to get into what this could cost you from a SLA / customer confidence perspective.

New Member
Posts: 6
Registered: ‎02-14-2017
Kudos: 2

Re: 3.9.15.8011 blocks DHCP

[ Edited ]

@cooler0918 wrote:

If you disable DHCP snooping on the entire site, you do not need to roll back. 



Where did you find that option?  I am not seeing any place in the settings to disble DHCP snooping.

New Member
Posts: 7
Registered: ‎05-12-2017
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Re: 3.9.15.8011 blocks DHCP

I was hit with this problem early on. I found the answer on this thread or a link off this thread. 

 

You will need to create properties file to make it permanent. I got information from this thread https://community.ubnt.com/t5/UniFi-Routing-Switching/Disable-DHCP-Snooping-on-USW/td-p/1510229

 

and adapted it it for my needs. 

New Member
Posts: 6
Registered: ‎02-14-2017
Kudos: 2

Re: 3.9.15.8011 blocks DHCP

Thank you @cooler0918!

 

This apperas to have fixed my issue, thank you for sharing.  It would nice if this was an option that was availble in the gui.

New Member
Posts: 27
Registered: ‎12-21-2017
Kudos: 4

Re: 3.9.15.8011 blocks DHCP

Do you know if this change survives future firmware updates?
New Member
Posts: 6
Registered: ‎02-14-2017
Kudos: 2

Re: 3.9.15.8011 blocks DHCP

I applied the change with the old firmware installed and then updated.  The settings propagated through to the new firmware.  If this will still work in the future I don't know, but I assume it will.

 

My undersatnding is that you have to make the change globally by creating the config file at the controller to make it permanent. (These instructions are near the end of the first page)  Acording to the other thread if you just change it on the switch via SSH it will be erased every time you provision the switch.  Also if you leave the mac address out of the command then it will apply to all switches in the system.

Established Member
Posts: 823
Registered: ‎07-23-2015
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Solutions: 47

Re: 3.9.15.8011 blocks DHCP

[ Edited ]

Are trusted DHCP server ports configurable in Unifi UI? If not, UBNT shouldn't be enabling DHCP snooping if you can't define server ports. It's a guarantee for problems.

Please don't forget to kudo helpful posts and mark accepted solutions accordingly!
jcm.me - Personal Site | Joyn.Tech - Consulting Site

Add Auto-Provisioning Support to UNMS
New Member
Posts: 15
Registered: ‎05-14-2016
Kudos: 3

Re: 3.9.15.8011 blocks DHCP

As far as I know snooping is not controllable via the UI. 

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