AP 250 not passing DHCP packets to clients

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  • Updated 1 year ago
We've been rolling out the new Wave 2 AC AP 250s to a couple schools with mixed success.  The problem that's been hitting us the hardest latest is dropping clients.  Looking through the Troubleshooting tab in HiveManager NG, we can see quite a number of clients with a "DHCP Server Unreachable" error.  Wired access is not affected so we've ruled out the possibility of our HP switches or Windows DHCP server being the problem since it only seems to be wireless clients.  We're running 7.0r2 and 7.0r1 firmware on the APs.  NAT/router settings are off with no firewalling so the AP SHOULD be running completely as a bridge.  Any known issues with APs messing with DHCP packets on the AP 250?
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Devin

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Posted 2 years ago

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Collin

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Devin, I've been seeing a similar issue with some recent deployments of AH250's. We're not seeing DHCP unreachable or timeout, but we are seeing lots of clients drop off and timeout. If they wait a few minutes they can reconnect. The problem seems to be especially pronounced when we have 30+ clients in a room. Haven't figured out the cause of the issue yet.  
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Chris Lockhart

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I am having a similar problem.  Any input would be great.
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Devin

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I another blog post an Aerohive rep said to try the "alg sip enable" command in the CLI as a workaround for some DHCP problems they've seen with their APs.  Make sure and do a "save config running current" for the changes to persist through a reboot too.  
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Sajid Abbas

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Any suggestions on how we can apply the config 'alg sip enable' through HM on AP250. The problem is even if we apply it through CLI, the next time I refresh/apply config from HM to the device it removes the cli command 'no alg sip enable'. We would have to repeat it again.

Any help would be appreciated.
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Devin

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I believe this problem was fixed in firmware version 7.1r1. Otherwise, you can apply CLI commands through HiveManager NG under Configure -> Network Policies -> Additional Settings -> and Supplemental CLI under Policy Settings.
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Frank O

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Have you found a solution to this issue?  We tried the '"alg sip enable" config, and this fixed the issues with all of the machines except for a handful, specifically Android Nexus and Pixel phones.  They are still having issues receiving addresses from the DHCP server staying stuck on "Obtaining IP address"
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Nick Lowe, Official Rep

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Hi,

Is there a reason you cannot update to HiveOS 7.1r1 that resolves the issue that required "alg sip enable" as a workaround?

Thanks,

Nick
(Edited)
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Arturo

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I am experiencing a similar problem to this one, and I've read on a couple of posts that sip alg enable should be entered in the CLI.

However, I don't see what this option has to do with DHCP.  Isn't Sip Alg only used for VoIP SIP packets?