I have deleted a lot of junk from the flash and things did not change. Since I have expected some filesystem error i have then reformatted disk0: sucessfully. Guess what, I still cannot copy any software image to the device.
Well, in case anyone is ending up in the same annoying situation....
I have cleared all the webvpn configuration and then - yeah - the device was willing to release some memory at last.
And it appeared to be enough to copy a current software image back onto the flash disk.
But I think the default 256MByte RAM of the older 5505 devices and even the 128MByte flash are way too small if it comes to webvpn. I have tried around with a spare device and with current 8.2.5-26 it is impossible to install the anyconnect-3-svc-images or a couple of anyconnect-2-images.
Yes, memory on older devices is too small when you start loading in latest software and supporting files. That's why Cisco has more memory (512 MB now on ASA 5505) on all newer shipments of those devices and all new platforms.
At some point, you should look at an upgrade to a current hardware platform. You are running the smallest ASA with the least amount of memory. Cisco hasn't announced a direct replacement for the 5505 but the 5525-X is very nice in comparison to the 5520 it replaced. Much higher performance and lots of memory. See the data sheet.
Table of ContentsIntroductionVersion HistoryPossible Future
UpdatesDocuments PurposeNAT Operation in ASA 8.3+ SectionsRule Types
Network Object NATTwice NAT / Manual NATRule Types used per SectionNAT
Types used with Twice NAT / Manual NAT and Network Obje...
Table of Contents Introduction:This document describes details on how
NAT-T works. Background: ESP encrypts all critical information,
encapsulating the entire inner TCP/UDP datagram within an ESP header.
ESP is an IP protocol in the same sense that TCP an...