为什么有些AP上线时一直卡在IL阶段

AC——FIT AP

AC进行版本升级时，有一台AP一直卡在IL阶段，无法升级成功。

在AC诊断里看，AP提示下载完成后一直在反复下载：

       Line 10301: %Mar 22 10:07:49:890 2022 WX3540H CWS/6/CWS_IMG_DOWNLOAD_COMPLETE: Downloading the image file wa5300.ipe for AP AP-2 through the CAPWAP tunnel is complete.

       Line 10306: %Mar 22 10:07:56:104 2022 WX3540H CWS/6/CWS_IMG_DOWNLOAD_START: AP AP-2 started to download the image file wa5300.ipe.

       Line 10462: %Mar 22 10:08:45:942 2022 WX3540H CWS/6/CWS_IMG_DOWNLOAD_COMPLETE: Downloading the image file wa5300.ipe for AP AP-2 through the CAPWAP tunnel is complete.

       Line 10476: %Mar 22 10:08:54:936 2022 WX3540H CWS/6/CWS_IMG_DOWNLOAD_START: AP AP-2 started to download the image file wa5300.ipe.

登录到AP上查看日志，AP一直在尝试去下载版本

===============display logbuffer===============  

Log buffer: Enabled

Max buffer size: 1024

Actual buffer size: 512

Dropped messages: 0

Overwritten messages: 2153

Current messages: 512

%Mar 19 15:35:17:926 2022 H3C CWC/6/CWC_IMG_DOWNLOAD_START: Started to download the image file wa5300.ipe through the CAPWAP tunnel to AC 172.18.1.2.

%Mar 19 15:36:08:556 2022 H3C CWC/6/CWC_IMG_DOWNLOAD_START: Started to download the image file wa5300.ipe through the CAPWAP tunnel to AC 172.18.1.2.

查看AP内存：

   ===============dir /all /all-filesystems=============== 

Directory of flash:

   0 drw-           - Mar 18 2022 22:56:16   core

   1 -rw-     5008384 Jan 01 2016 00:00:00   wa5300-boot.bin

   2 -rw-    16177152 Jan 01 2016 00:00:00   wa5300-system.bin

30720 KB total (912 KB free)

老版本两个bin加起来是：21185536字节

而AP上的剩余空间：(912 KB free)

且新版本的两个bin加起来是：23636992字节

由此得出结论：这个AP上存在core文件，导致AP上的flash空间不足，从而AP下载版本不成功。

ap在AC上下版本的时候，我们要求：新的版本大小 <= 老版本+剩余空间

通过格式化后，该AP重新上线成功