Having trouble with joining existing WLAN with Cisco AIR-AP1815I-E-K9

[Soxi]

Hello Cisco enjoyers, I am having some issues with my APs again.

This time, it is about 2 1815I that are unable to join the existing WLAN and the WLC that are working well on their side, despite being in the good VLAN and having the good port configuration (maybe not but to me it is, I also replaced the IPs to keep some secrecy).

More precisely, I had to replace the first one by a 9105 even if it was functional at that time, it was just to upgrade it, but then we decided to come back on our choice and put the 1815 back where it was. And this is where I'm lost. 

I've checked the configurations and I replicated them to a testing port next to me that could be considered as a copy of the one where the AP should be, and it still gets rejected or something else, but this is where I need your help.

I'm having a bit of a tough time reading through the logs and understanding them so I thought it would be simpler if you could help me with it.

The logs I get from one of them (the other AP seems to be in the same case but I sent it on another site thinking it was functional) are in the attached file.

Thanks in advance for your help !

[marce1000]

 - What is the WLC model and software version running on it ? Note that in certain cases the AP image must be provided through a tftp server because of lack of space on the controller to hold AP images , 

 M.

[Rich R]

Agreed with Marce - based on the limited info you provided it looks like:
- You're using Mobility Express for your WLC (in other words another AP)
- You probably upgraded the ME to 8.10.x version to support the 9105 APs
- Now the 1815i APs need to download the same 8.10.x version as the ME WLC is running
- You need to setup a TFTP server with the correct version AP image on it for the APs to download from as per the ME config guide.

Don't forget to always provide info on what controller you are using and what version of software it is running on.

[Soxi]

Hello, thanks for your messages.

I didn't think about sharing the WLC configuration but here it is in the attached file.

If I get it correctly, the main cause would be a difference in the version of the AP images of the APs.

I thought about it and decided to upload the version my tutor gave me by TFTPD before posting, but it just seems that the version of the image I uploaded was just too old in fact. 

To be honest, my main weakness in this domain is the fact that things are still quite unclear in my head, which makes me struggle to take a step back when needed.

[Rich R]

So your controller (I'm guessing from the name and filename that it's an 1815 AP running ME) is running 8.10.183.0 code
Your new AP is running 8.5.151.0 so it needs to be upgraded to the same version.
So you need to unzip the contents of the zip file at https://software.cisco.com/download/home/286306794/type/286289839/release/8.10.183.0 on your TFTP server, then configure the TFTP section of the ME WLC to point to that TFTP server so that the AP can download the image from there:
https://www.cisco.com/c/en/us/td/docs/wireless/controller/technotes/8-2/b_Mobility_Express_Deployment_guide/b_Mobility_Express_Deployment_guide_chapter_01000.html#task_4387C8D3ADCA4D9EA365763A1DA5B2E2

There is a known bug with ME upgrades that it sometimes runs out of flash space during the upgrade causing the upgrade to fail.  In that case you should convert the AP to CAPWAP, install a CAPWAP (lightweight) image on the AP:
https://software.cisco.com/download/home/286306794/type/286289839/release/8.5.182.0
And then convert the AP back to mobility express with the ME tar file from the download link above (where you got the zip file).

[Soxi]

Hello Rich R. and thanks for the quick reply ! 

You're right, the WLC model is the same as the new AP I want to set up as written in the title, the 1815I-E-K9.
I am going to try your solution.

I just wanted to know if I had to compress back all the files in a .tar file before uploading it to the AP ?
If not, what file from the zip one do I have to indicate in the command line ?
(I attached a screenshot with the .zip file that I unzipped in the same folder and compressed it back in a .tar file)

I'm also doing the TFTP between my laptop and the AP directly, does it matter if it doesn't go throught the WLC in the process ?

And for my last question, do you have any idea why it was working until I unplugged it to place a 9105 instead, then stopped working when I wanted to put it back at the same place ?

Thanks again for everything !

[Rich R · Accepted solution]

> I just wanted to know if I had to compress back all the files in a .tar file before uploading it to the AP ?
> If not, what file from the zip one do I have to indicate in the command line ?
NO!  The zip file must be unzipped on the TFTP server to allow the AP to upgrade automatically when instructed to be the ME WLC.  All you do is unzip the file on the TFTP server.  You do not specify any filename - the WLC does that when it instructs the AP to fetch the file from the TFTP server.  The 1815 uses "ap1g5"

> I'm also doing the TFTP between my laptop and the AP directly, does it matter if it doesn't go throught the WLC in the process ?
Well if you disconnect it from the WLC then the WLC can't direct it to the TFTP server.  That means you will have to do a manual upgrade using the AP CLI with the correct filename as specified in the info file (apname_decoder.inc) which you'll also find in the zip file.

> And for my last question, do you have any idea why it was working until I unplugged it to place a 9105 instead, then stopped working when I wanted to put it back at the same place ?
I already answered that twice above - you upgraded the software from 8.5.151.0 to 8.10.183.0.

[Soxi]

Okay, I definetely need to be more precise, this is my bad on this.

Currently (and for the 3 or 4 times I've had to upload an image on an Cisco AP, either 1815 or 9105, I used my laptop as a TFTPD server, directly connected to the AP, in an isolated network (or in the current case I do it across our network since the two devices can already communicate).

So I understood what you meant by unzipping the file on the TFTP server and uploading it on the WLC which will do it alone. I just didn't know the WLC was doing that, since I've never had to touch the WLC on this 1815i model.

The thing is even if I knew how to do it, my main issue is that the "not working" client AP wont join the WLC even if they are in the same network, so I believe this means whatever image I upload to the WLC, the AP wouldn't be able to catch it just like in the current situation.

This is why I wanted to do it with the "not working" client AP next to me, with a CLI opened on my laptop to directly upload the image from my laptop to the client AP by TFTP since my server is my laptop.

In the end, my issue was knowing which file of the .zip folder had to be uploaded on the AP, and I thought about a .tar file because of this tutorial I found earlier (but now I understand the difference between the two files you can download and between conversion and upgrade) : How to convert/upgrade a Cisco AiroNet 1815i from CAPWAP (Controller-based) to Mobility Express (standalone) - Spiceworks

But thanks to your indication, I found in the decoder.inc file which one I had to upload.

Now my AP has been linked to the WLC, I just have to follow this for the other one. It looks like the main part of the problem was me not understanding everything and lacking of knowledge on this subject but at least I'm improving on it.

Thanks a lot to you guys !