[mythtv-users] Please help me move my backend to new host/hardware.

[Ram Ramesh]

On 3/24/23 10:26, Ram Ramesh wrote:
> All,
>
>  I have a mythtv setup with one backend and several frontends. The 
> backend machine also runs a frontend to test any issues locally. They 
> all run some version of debian with mythtv packages installed over 
> standard release. Currently they all are on debian bullseye with 
> possibily running more recent kernels due to the need to support more 
> modern processors. My tuners are HDhomerun networked on the same 
> subnet. There are two - one 2-tuner and another 4-tuner with static IP 
> assignment from my  home DHCP server. My current backend is also on a 
> static IP assignment. Other frontends are on dynamic assignment.
>
>   However, my backend is old (10+ years) and in need of HW upgrade. 
> Towards this, I have built a new machine with intel z690 MB and a core 
> i3-13100. I installed debian testing and ran a complete check to make 
> sure key hardware components work as expected. I also checked kernel 
> 5.19 supports all that care about in my new machine. I am at a point 
> to move my backend SW setup to this machine. To support this I have a 
> new and unused partition of correct size in the new machine's disk. 
> Both current and new hardware use UEFI boot and I do not have any 
> legacy BIOS boot in any of my home machines.
>
>  My plan is to make image copy of the current installation, restore on 
> the partition created for this purpose and set it up.
> Let us call the test installation (debian testing to check the 
> hardware) as _new-base_ and backend image copy restored on new 
> hardware as _new-backend_. We will use _current-backend_ to refer to 
> the system that is currently running and serving from the older 
> hardware that I want to replace.  I plan to proceed this way and 
> please let me know if I am making any mistakes. (These steps are 
> inspired by this: https://www.mythtv.org/wiki/Backend_migration)
>
>  1. Shut down all frontends
>  2. On the current-backend, make a fresh db backup and disable backend
>     service (systemctl disable mythtv-backend)
>  3. Reboot current-backend machine using some rescue boot usb and make
>     image copy of the current install on to a spare disk. Shutdown the
>     backend machine completely and do not boot it at all again.
>  4. Boot new-backend hardware, bootup new-base installation, image
>     restore backend on to its designated partition
>  5. Fsck this restore to make sure everything is ok, mount it, fix
>     fstab, hostname and few other essential items in the restore
>     image. Also make sure using symlinks storage directories now point
>     to local disk.
>  6. Run update-grub on new-base install so that new-backend image
>     becomes a choice up on grub prompt on a reboot.
>  7. Reboot the image copy (new-backend) update-grub and
>     update-initramfs -u and reboot back into new-backend
>  8. Since backend.service was disabled before image copy, note backend
>     is running yet. Run mythtv-setup and fix master-backend name and
>     IP and any  other essential items.
>  9. Transfer storage drives from current-backend machine to
>     new-backend drive and make sure symlinks made in step 5 are
>     adjusted to point to correct directories.
> 10. After double checking, enable backend-service and start it. Go to
>     a nonfrontend host, pull up mythweb and check that you can
>     connect/view the status on the new-backend. Ensure all tuners are
>     visible and you can see the listing.
> 11. Add a recording to see if things work as expected.
> 12. Start the frontend on new-backend machine enter setup and point it
>     to new-backend. Watch live-tv and pull up the new recording made
>     to check everything is ok
> 13. Review status of backend recordings/rules etc to make sure
>     everything is in order.
> 14. Boot up other frontends and point to the new-backend and test it.
> 15. Wait a week for this new setup to work as expected and then
>     permanently wipe the current-backend install so that it can never
>     be booted to cause any confusion.
>
> Please let me know if I missed any step.
>
> Since I used UUID for all mounting (or partition reference), I chose 
> image copy/restore instead of tar to create and restore the 
> installation. Let me know if you think that is a bad choice also.
>
> Regards
> Ramesh
>
>

Unfortunately, it appears that tuners are tied to either backend name or 
IP address. So, unless you name your new hardware/host the same host 
name as the old one and force DHCP to assign the same IP address, the 
migration process has little chance of success. Of course, you can give 
a new name, but capture card and input connections will be lost. You 
will have to manually rebuild it, but I am not ready for that. So, I 
caved in and used same hostname and IP address.

Are there any scripts available that will change host/IP entries in the 
database as part of restore? BTW, mythweb also gets confused if IP changes.

I have moved to new hardware, and first recording is in progress. Old 
recordings and mythweb works as before.

A couple of nonmyth issues related to sas9211 hba card. It nolonger has 
the initial greeting message from its BIOS. It also seem to prevent 
shutdown/reboots.  I have to bruteforce power button poweroff. May be I 
need a newer kernel or a video card with vesa vga bios. However this is 
not a myth issue and therefore only FYI.

Regards
Ramesh
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mythtv.org/pipermail/mythtv-users/attachments/20230325/c340ee83/attachment.htm>