Jack wrote: > On 2018.12.06 15:58, Dale wrote: > [snip...] >> My concern is this tho. I have my old CPU still installed and >> everything is compiled based on that. So, I'm stable with the old >> CPU. However, when I shutdown, take out the old CPU and install the >> new one, I'm concerned it may not boot at all because of the change >> or may boot but be very unstable. I recall years ago being able to >> set up the flags in such a way that it can run on virtually any CPU >> but it's been a long time ago and I don't know if it is needed or >> not. My hope was, someone did a very similar upgrade and can say for >> sure if it works or if I need to do things before changing the CPUs >> to make sure I can boot and be stable. If I can just get a stable >> console, I can do a emerge -e world and get the OS inline with the >> CPU. I'm just concerned whether I will have that or not. >> > [snip...] >> >> I just don't want to swap CPUs only to find out I've got to swap back >> because my system won't boot at all. Heck, it may even fail to load >> the kernel itself for all I know. > I once made the mistake of getting a whole new (used...) PC and just > moved the HDD from the old one to the new, without thinking about any > of this. Of course it wouldn't boot at all, because I was switching > from an AMD to an Intel CPU and had set all flags accordingly in the > old box. In your case, as long as you include any flags necessary for > the new CPU, and remove any flags for features the new CPU does not > have, you should be good. (I know that sounds simple, but does ignore > how you find that info.) Given your two CPUs are relatively close > (unless I misread something) there should be little if anything > critical to change. > > However, if you have a live DVD, (or on USB stick) that will always > boot, and you can then do a chroot and reset flags and start > recompiling whatever might fail. I actually think the kernel IS the > likely failure if any, but once that boots, you should be good to > recompile whatever fails. (Yes, toolchain stuff might be an issue, > but again, just boot back to the live DVD.) You may need to reboot a > few times, but you won't need to swap the old CPU back in. > > Jack >
I've tried that too. Heck, sometimes that doesn't work even with windoze. My concerns are sort of along those lines tho. I don't have and can't find the current flags for the new CPU so I don't know what to do flag wise. I'm not sure that there is even a common setting but suspect there is. If I can get the kernel to boot and login at a console, even with no X, I can rebuild from there, provided everything works toolchain wise. I guess this is a good time to make sure my sysrescue and other tools work. That slipped my mind completely. Thanks for the reminder. Hmmm, I need to check on the current mount and chroot process for this too. Thanks. Dale :-) :-)
