You need at least 128 meg of memory and 28 meg of flash to run 12.4T code , this is minimum and may not be enough if you are running many features on the box . Do a show version to see how much memory you have .
Glen makes a good point about the memory and flash requirements. The error messages that you posted look much more like memory problems that flash problems. My guess is that the code that you loaded was a significant step up from the code that was on the router before and that you do not have sufficient memory to run this version. It looks like your choices would be to upgrade memory or to go back to somewhat older code.
I checked the requirements for running c870-advipservicesk9-mz.124-6.T6.bin and as Glen indicated it does require at least 128 MB of memory and 28 MB of flash. If you post the output of show version it will show what you have on that router.
Desire to create Terminal Server ("TS" in this document) out of 2811 Cisco Router with HWIC-16A card (with Octal cables)
Desire to use SSH over Telnet
TS is ip'ed, SSH access configured (to the TS)
Python based Script to BULK Import/Delete devices using Cisco Prime API
Check my Repo on GitHub for all the details ( see below link )
ASR9001 DC chassis doesn't prints a syslog incase voltage for one of the Power Modules goes below certain threshold. Because of this the monitoring of PowerModule for any failure becomes difficult. ...