Cisco AP Flash corruption issues.

Cisco AP Flash corruption issues.

https://www.cisco.com/c/en/us/support/docs/field-notices/703/fn70330.html

Apparently flash corruption is common on some APs - These are the only Cisco IOS AP models affected: 1600, 1700, 2600, 2700, 3600, and 3700 Series APs.

Some Cisco IOS® Access Points (APs) report no flash access or file system corruption after an AP reboot. This is most commonly seen when a Wireless LAN Controller (WLC) is upgraded.

The corruption can cause these conditions on the AP:

The AP is unable to save the configuration.

The AP is unable to perform an upgrade.

The AP loses configuration.

The AP is stuck in a booting loop.

The AP is in bootloader status.

There is a wireless poller that can help detect it.

To fix it - if you can SSH in or get to ROMMON through console you can try and fix it

https://www.cisco.com/c/en/us/support/docs/wireless-mobility/wireless-lan-wlan/213317-understanding-various-ap-ios-flash-corru.html#toc-hId--1175248419

If you can get to the AP through Rommon - this is the method I ended up using.

can get into rommon via console by holding the mode button while booting the AP

to do this you will need an a console connection and IP connection to the AP to load the new firmware image.

You'll need a TFTP server running on your computer hosting the firmware image. We're loading the recovery image which is c3700-k9w8-tar.153-3.JF14.tar for the 1700s for the WLCs running 8.5.171.0.

Once in rommon

set

IP_ADDR <IP Address>

NETMASK <mask>

DEFAULT_ROUTER < default router >

tftp_init

ether_init

flash_init

! then try

format flash:

tar -xtract tftp://<IP address>/<file name> flash:

set BOOT flash:/<file name>

boot

!! example

set

DEFAULT_ROUTER=10.1.1.1

IP_ADDR=10.1.1.20

NETMASK=255.255.255.0

tftp_init

ether_init

flash_init

format flash:

! you can also do a fsck flash:

tar -xtract tftp://10.1.1.8/c3700-k9w8-tar.153-3.JF14.tar flash:

set BOOT flash:

boot

If you have an SSH/telnet Connection -

If you can get in through SSH and formatting flash is working through there then you can do this

NOTE: once you format the flash if you can't get the new image on their successfully you're going to need console access to fix the issue.

!stop capwap auto reboot

AP# debug capwap console cli

AP# debug capwap client no-reload

Format flash and if successful then you can continue to the next step otherwise you'll probably need to try and do it through ROMMON

AP# format flash:

Load a recovery image. Like c3700-k9w8-tar.153-3.JF14.tar for the 1700s 8.5.171.0 WLCs

archive download-sw /overwrite tftp://<IP address>/<file name>

If desired you can check the MD5 on the recovery image. If it doesn't match you can try downloading it again. Otherwise, you're probably going to need console access when the AP reboots.

AP# verify /md5 flash:/<image directory>/<image file>

Set boot variable to newly downloaded Recovery image:

AP#show boot

conf t

AP(config)#boot system flash:

Fix Edge IE Mode Expiration

 https://lesferch.github.io/IEModeExpiryFix/

Cisco WLC - Issues with APs Joining the Controller and Upgrading Firmware After 12/4/2022

 Any IOS-based AP (1700/2700/3700/1570) downloading a new image from WLC running any version after December 4th 2022.

The AP can leave and re-join any WLC after Dec 4th 2022 provided it does not have to download a new image, if it has to download a new image (regardless of the version, 9800 IOS-XE or AireOS), it will fail.

For any WLC that has APs stuck in the downloading state:

• Disable Network Time Protocol (NTP) on the WLC and manually set the WLC date/time to a date before December 2, 2022. The Cisco IOS AP will then be able to download and validate the image, install the new image, and join the controller. Once the AP has joined the controller, NTP can be re-enabled on the controller to assume the correct date and time.

https://bst.cloudapps.cisco.com/bugsearch/bug/CSCwd80290

https://www.cisco.com/c/en/us/support/docs/wireless/aironet-700-series-access-points/218447-ios-ap-image-download-fails-due-to-expir.html

https://www.cisco.com/c/en/us/support/docs/field-notices/725/fn72524.html

Autohotkey (AHK) Reformat MAC Addresses

 Here is an AHK script to reformat MAC addresses. It takes a MAC address from the clipboard with :, -, ., or no separators and reformats it into several options each on their own line in the clipboard.

Output:

AA:AA:BB:BB:CC:CC
AA-AA-BB-BB-CC-CC
AAAABBBBCCCC
AAAA.BBBB.CCCC

Script:

;reformats MAC addresses. Press ALT+Shift+M

!+m::

Clipboard := StrReplace(Clipboard,"-","")

Clipboard := StrReplace(Clipboard,":","")

Clipboard := StrReplace(Clipboard,".","")

sleep 10

var1 := Clipboard 

var2 := RegExReplace(Clipboard,"(?<!^.)(..)(?=[^$])","$1:")

var3 := RegExReplace(Clipboard,"(?<!^.)(..)(?=[^$])","$1-")

var4 := RegExReplace(Clipboard,"(?<!^.)(....)(?=[^$])","$1.")

var5 = %var2%`n%var3%`n%var1%`n%var4%

Clipboard := var5

return

Windows ARP Scan Utility

ARP scanning a subnet in Windows can be done with Nmap but some AV/security utilities don't like Nmap and it's a bit heavy. arp-scan-windows can be used as a simple standalone program to scan a subnet. 

Link: https://github.com/rsweet2/arp-scan-windows

Cisco WLC - Use AP as a Sniffer

And send traffic to remote wireshark. 

https://www.cisco.com/c/en/us/support/docs/wireless-mobility/80211/200527-Fundamentals-of-802-11-Wireless-Sniffing.html#anc12

Wireshark Capture filter - host 10.1.1.3   more info

1) WLC / AP side

Here are the steps in order to collect a trace using a sniffer mode LAP

• Configure the AP in Sniffer mode:

The AP will reboot and it will not be able to serve clients.

• Once the AP has re-joined the WLC, configure the radio of the AP (802.11b/g/n or 802.11a/n):           
  • specify the sniffer IP address
  • select the channel
  • enable sniffing

• The sniffer will receive the 802.11 traffic encapsulated using the airopeek protocol, from the WLC management IP address with source port UDP/5555 and destination UDP/5000

2) Sniffer side: Wireshark

If using Wireskark to receive the traffic, follow the steps below:

• Set the capture options to receive only traffic coming from the sniffing AP. If you set the filter only for port UDP 5000, you will miss IP fragments in the capture if the AP has to fragment the packet (which will happen if it sniffed a 1500 bytes long frame to which it needs to add PEEKREMOTE encapsulation):

This filter is optional but strongly recommended as it excludes all the non-wireless related traffic from the capture. Consider that the WLC sends traffic to a UDP port there’s no application listening on the sniffer side; this results in having a ICMP port-unreachable response for each packet received from the WLC.

Although this is expected, the filter above helps to exclude also this traffic which is useless and so it can only cause the trace to be bigger and more difficult to read.

• Then, start the capture:

• The captured traffic has to be “decoded as..” PEEKREMOTE in order to be able to see the 802.11 traffic:

• The 802.11 traffic will now be visible:

The RF info shown above (e.g. the channel, signal strength, noise..) are added by the AP.

Cisco CUE Service Module - Show console output without logging in

 test service-module integrated-Service-Engine 0/0 console 

let's you see the most recent console output without needing to actually log in.

https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/unity_exp/rel8_6/install/CUE_86_install/boothelp.html

Problem - No Session

You are unable to open a session to the CUE module or you do not see any output on the console.

Solution

You can use this command in order to check the console messages on the CUE module without the need to open a session to it:

Router# test service-module service-engine slot/unit console

By default, this command displays the most recent 80 lines stored in the console buffer. However, it is possible to specify an offset of greater or less than 80, or to view all the messages stored in the console buffer with this command:

Router# test service-module service-Engine slot/unit console ?
  <1-20456>  Offset into console buffer
  all        Entire console buffer

Sonicwall - Get Complete Config via CLI

 no cli pager session 

show current-config

Sonicwall Multiple WAN Subnets Configuration

 Configuration information for configuring multiple WAN interfaces 

Should work for Comcast EDI (Fiber) circuits

https://www.sonicwall.com/support/knowledge-base/configuring-multiple-wan-subnets-using-static-arp-with-sonicos-enhanced/170503911164326/

https://www.carlc.com/modules/Wordpress_Blog/configure-sonicwall-router-for-comcast-business-fiber-ethernet-multiple-ip-segmentsranges/

Pretty sure this should work too - assigning it to a DMZ zone http://starforce.cyou/

Sonicwall Firewall Configuration Decode

 base64 -d -i "SonicWallConfig.exp" | sed 's/&/\n/g' > SonicwallConfig.txt

https://www.sonicwall.com/support/knowledge-base/how-to-get-the-configurations-of-the-firewall-based-on-the-exporting-exp-file/170503330364045/

Sonicwall Firewall - Gen 7 Diag Page

 To access the diag page on gen 7 firewalls go to 

/sonicui/7/m/mgmt/settings/diag

e.g.   https://10.1.1.1/sonicui/7/m/mgmt/settings/diag

Get DTMF to Work Between a Switchvox PBX and Vega Gateway

 Change the Switchvox PBX to use Inband DTMF in the SIP provider settings for the Sangoma gateway provider. 

The default on the PBX is RFC4733 and the default on the gateway is RFC2833 so I'm not sure why this is required. 

This worked on a Vega 60Gv2 gateway. 

   

Find hardware version of Raspberry Pi from the command line

 

See instructions here: https://elinux.org/RPi_HardwareHistory#Which_Pi_have_I_got.3F

Run

cat /proc/cpuinfo

look for revision and look it up on above page

! or 

cat /proc/cpuinfo | grep 'Revision' | awk '{print $3}' | sed 's/^1000//'

! web version - not always accurate/updated though and not well documented

rev=$(awk '/^Revision/ { print $3 }' /proc/cpuinfo) && curl -L perturb.org/rpi?rev=$rev

Windows Server Activation

Several Windows Server 2019 installs wouldn’t let me activate them normally. To do it, launch an elevated command prompt and use this command - 

cscript c:\windows\system32\slmgr.vbs /ipk <product-key>

Cisco WLC AP Certificate Ignore

 For 7.4.140.0 and later:

(WLC)>config ap cert-expiry-ignore {mic|ssc} enable

https://community.cisco.com/t5/wireless/help-me-problem-with-wlc-and-ap/td-p/1958404