Disable mesh stranding prompt when disabling 802.11a?

[wififofum]

I'd like to TFTP download a config file that will restrict 802.11a channel use to 17dB channels.  Is it possible to bypass/process the annoying mesh stranding (y/n) prompt from within a config file?  Or perhaps disable mesh (or prompting) altogether? wlc>config 802.11a disable network Disabling the 802.11a network may strand mesh APs. Are you sure you want to continue? (y/n) Thanks, --Bruce Johnson

[Stephen Rodriguez]

No, that error message is there as a CYA.  If it wasn't there and someone stranded the AP and lost revenue, they could try to sue for the loss.  Think of this like the 'Hot Coffee' marking when you go to McDonalds.

That being said, if you pull off the config, make the change and then upload.  When the WLC reboots it will have the settings you want, and you won't see that message.

HTH,

Steve

[wififofum]

Thanks Steve, I just uploded a modified pre-existing config with "config advanced 802.11a channel delete" commands in it.  The channels still sppear under DCA. I guess I should be thankful the "shutdown" command doesn't have this requirenment ;P  Why is the WNBU so lawsuit-sensitive? I assume the command interpreter is complaining (albeit silently where I can't see it) that the 802.11a network needs to be disabled prior to deleting any channels.  I put a "config 802.11a disable network" in the top of the file on previous attempts, and I assume the prompt was spoiling the show.  I didn't ask for mesh support. This worked fine in 4.x (before the trains merged). Its a new day each time a config file is uploaded, so I don't see any way of getting around this.  How does the WCS get around this for controller auto-provisioning?  Or is the assumption that channels aren't changed? --Bruce

[wififofum]

The same prompting issue exists with these commands as well as with disabling the 802.11a network.  Can I sue for operational distress?  Why can't we have a one-shot config file?  Its how network devices are supposed to facilitate limited maintenance windows. config certificate generate webauth config certificate generate webadmin

[wififofum]

Same roadblock with QoS Profiles as well, since it depends on the radios being disabled.  So are we SOL with the possiblity of a single comprehesive config file in 6.x and above?

[Stephen Rodriguez]

With wireless, when you change the allowed channels and the QoS, the WiFi has to go down, so that it can come up on the right variables.

So, what you can do, is get one WLC configured exactly how you want it, then upload the config to a server.  This config is ascii so it can be edited.  All you would need to do, is change the IP addresses on the interfaces, and you have the same config for every WLC.  upload this conifg, then reboot.  When the WLC comes back online, it will have the settings that you want.

Otherwise, you are changing a live config, that yes, requires the 5GHz/2.4Ghz to be disabled when you want to change what channels are used as well as what .1p marking you are going to set.

[wififofum]

That's exactly what I'm doing (uploading edited config files).  Everything else works fine, but I am not seeing the channels removed, nor the certs generated, as the return character to execute the next config line cancels these operations. From my observations, it appears undesired channels have to be deleted, as the default is all channels, except for UNII-II extended.  I have tried explicitly adding the desired channels only to see if this implicitly omits the others, and it does not.  I suspect this is also liklely due to the radio having to be disabled first (that's how the CLI reacts anyway). For channels to be deleted the radio first has to be disabled, which requires manual intervention in 6.x and above due to the mesh.  The only time I believe the radios can ever be disabled on bootup is if the 802.11a/b network isn't enabled in the startup configuration wizard.

[Stephen Rodriguez]

Ok, when I say upload the config, I mean take a backup of the config, and edit that file, then dowload it back to the controller and reboot.

it sounds like you are sitting at the

config>

prompt cutting and pasting the stuff in.

[wififofum]

Nope.  I'm TFTP downloading the config.  I run a debug transfer trace enable during the download to see if anything odd happens and a show invalid-config to see if anything didn't take after reboot.  I think I'll have to paste the config cert generate, 802.11a disable network and 802.11a advanced channel delete commands post-reboot.

[wififofum]

Steve, You made me think about this some more so I disabled the 802.11a network first then downloaded the config in the hopes the changes would be made and saved with the channels removed.  Alas, no joy.    Can someone from Cisco weigh in on this?  What happens when a config file is downloaded?  Is it simply parsed for correct syntax and the controller reloaded with the config and controller at default values?

[wififofum]

FWIW, between these statements it seems mucking with 802.11 channels and settings in the config file, or with other commands with prompts such as cert generation, is not possible. The file is converted to XML and then applied, presumably in the command line order it was received. 

WLC 6.0 Configuration Guide states

The controller does not support incremental configuration downloads. The configuration file contains all mandatory CLIs (all interface address CLIs, mgmtuser with read-write permission CLIs, and interface port or LAG enable or disable CLIs) required to successfully complete the download. For example, if you download only config time ntp server index server_address as part of the configuration file, the download fails. **Only the CLI commands present in the configuration file are applied to the controller, and any configuration in the controller prior to the download is removed.**

The controller converts the configuration file to XML format, saves it to flash memory, and then reboots using the new configuration.  CLI commands with known keywords and proper syntax are converted to XML while improper CLI commands are ignored and saved to flash memory.  Any CLI commands that have invalid values are replaced with default values. To see any ignored commands or invalid configuration values, enter this command: show invalid-config

Source:

http://www.cisco.com/en/US/customer/docs/wireless/controller/6.0/configuration/guide/c60mfw.html#wp1063907

***************************************************

Command ref for the config 802.11a enable command states

Defaults Transmission is enabled for the entire network by default.

Source:

http://www.cisco.com/en/US/customer/docs/wireless/controller/6.0/command/reference/cli60.html#wp7214873

[Rob Huffman]

Hey Bruce & Steve,

Very interesting and enlightening thread + 5 each

Cheers!

Rob

[wififofum]

Thanks Rob and Steve,