EAP Changed IP address, Log Entry

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EAP Changed IP address, Log Entry

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EAP Changed IP address, Log Entry
EAP Changed IP address, Log Entry
2020-08-21 20:29:01 - last edited 2020-08-21 21:45:34
Model: EAP245  
Hardware Version: V3
Firmware Version: 2.4.0 Build 20200117 Rel. 39932

Our EAPs occasionally trigger a “changed LAN IP and mask” log entry.

Does anyone know what causes this?

It’s followed about 40 seconds later with a “connected to EAP200” log entry.  

My concern is that the EAP is actually disconnected from the LAN during these 40 seconds.

 

Thanks,

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#1
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Re:EAP Changed IP address, Log Entry
2020-08-21 23:28:03

@Bobby1859, could be expiration of the DHCP lease. Use static IPs for stationary devices to avoid this renewal of the IP.

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#2
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Re:EAP Changed IP address, Log Entry
2020-08-22 00:26:32
Thanks, I'll check that out.
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#3
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Re:EAP Changed IP address, Log Entry
2020-08-22 15:47:17

@R1D2 

 

R1D2 wrote

@Bobby1859, could be expiration of the DHCP lease. Use static IPs for stationary devices to avoid this renewal of the IP.

The AP I’m focused on has been set to static IP since it was installed back in about Jan 2020.

 

The operator field in the log is blank so I don’t know what originated this Change IP action.

 

So my question now is: Why is the AP (or something) trying to change it’s LAN IP and mask when it is set to static? 

 

Here’s the text from the log:

 “Rm C120 / C121 Ceiling (mac address) changed LAN IP and mask to 192.168.1.12/255.255.255.0”. (it was already .12)

 

(I found two other APs that were installed last weekend in our scramble to get this small school ready for online classes,  that were left in the default DHCP mode.  I changed those this morning to static)

 

Thanks

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Re:EAP Changed IP address, Log Entry
2020-08-22 16:00:23

 

Bobby1859 wrote

@R1D2 

 

So my question now is: Why is the AP (or something) trying to change it’s LAN IP and mask when it is set to static?

 

I see this message on sites with either a flaky network or which use static MAC/IP mappings in DHCP.

I don't see such messages in stable networks with static IPs set directly in the EAP.

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#5
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Re:EAP Changed IP address, Log Entry
2020-08-22 16:12:46
Thanks, I'll look into that.
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#6
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Re:EAP Changed IP address, Log Entry
2020-08-22 17:14:12
We do not use MAC/IP mapping in DHCP. We set the EAPs to static IPs using the Omada controller, which is not directly to the EAP. But we assume Omada is handling that correctly. We don't have network performance or stability issues, or things that would look flaky. But even if we did, why would an EAP, directly set to static AP, at least through Omada, change it's IP and mask? Thanks
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Re:EAP Changed IP address, Log Entry
2020-08-22 17:56:49 - last edited 2020-08-22 18:07:41

 

Bobby1859 wrote

But even if we did, why would an EAP, directly set to static AP, at least through Omada, change it's IP and mask?

 

Yes, Omada controller sets the IP in the EAP directly; it's stored in the EAP's flash.

 

Everytime the EAP is disconnected (even if it is only for a few seconds), the controller will go through the »Provisioning« and »Configuring« cycles again when the EAP is back on-line. There is a short delay until this re-configuration happens after the EAP did come back.

 

For example, I just disconnected my EAP from the network for 4 seconds. This is what I get in the log:

 

EAP3(B0-95-XX-XX-XX-XX) connected to LAN                                            2020-08-22 19:50:23

EAP3(B0-95-XX-XX-XX-XX) changed LAN IP and mask to 192.168.1.210/255.255.255.0      2020-08-22 19:49:55

 

Note that the EAP already had the static IP 192.168.1.210 before the short disconnect. Storing the IP in the EAP allows to still use the EAP if the connection to Omada controller drops, but the connection to the Internet router is still intact. So the EAP needs not to disconnect completely from the network, but only from the controller to cause this message to appear in the log.

 

Now imagine a controller running on a desktop system which goes to energy saving mode then and when ...

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#8
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Re:EAP Changed IP address, Log Entry
2020-08-22 18:54:18
Thanks, this helps. So, the “Changing LAN IP and mask” log entry reflects a normal process in the provisioning/configuring cycle when the EAP reconnects to the controller. And we do see the connected log entries, they say “EAP… connected to OC200_name” So, we use the OC200, not the PC based controller, and it’s POE switch is connected to a battery backup. But, shouldn’t I see log events if the connection between the EAPs and OC200 is lost?
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#9
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Re:EAP Changed IP address, Log Entry
2020-08-22 19:24:13 - last edited 2020-08-22 19:25:58

@Bobby1859,

 

yes, you will see a disconnect state after few minutes.

 

Does your PoE switch provide an af or an at power budget?

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#10
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Re:EAP Changed IP address, Log Entry
2020-08-22 20:17:23
I'll check the PoE switch when I'm back over there Monday. Also the cable between the OC200 and switch. It's a smart switch, so maybe it will tell us something. In any event, I'm relieved that these events are likely disconnects between the OC200 and the EAPs that do not effect the EAPs service to users or network connections. Thanks
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#11
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