Hi romeo.r,
Use the alternate statement instead of '1' statement .
request system snapshot media internal slice alternate
request system reboot slice alternate media internal
If still does not work , please show me the output of :
request system snapshot media internal slice ?
Use KB23180 for further information
And can you share us the ourput of :
show system snapshot media internal
show system snapshot media internal slice 1
show system snapshot media internal slice 2
Please be aware that if your switch is part of virtual chassis you can use :
request system snapshot media internal slice alternate member member-id