How to hibernate

_posts/2021-01-04-how-to-hibernate.md

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+---
+layout: post
+title:  "How to Hibernate"
+author: Ta180m
+tags: ["Linux"]
+---
+
+
+If you dual-boot, hibernation is a necessity. Need to use the other OS for a few minutes? No problem, just hibernate, and when you boot your original OS again, you'll be back where you left off.
+
+However... It's 2021 and there still isn't an easy way to enable hibernation on Linux. Sad.
+
+Anyways, here's a rough outline of the procedure:
+
+## Make a swap file
+
+You generally want your swap file to be at least as big as your RAM, and if you do a lot of swap-intensive stuff, you might even need a bigger swap file.
+
+```sh
+# create a swap file
+sudo swapoff -a # disable all swap
+sudo dd if=/dev/zero of=/swapfile bs=1M count=8196 # create a 8GiB swap file
+sudo chmod 0600 /swapfile
+sudo mkswap /swapfile
+
+# add it to /etc/fstab
+sudo sed -i '/swap/{s/^/#/}' /etc/fstab
+sudo tee -a /etc/fstab<<<"/swapfile  none  swap  sw 0  0"
+```
+
+## Set kernel parameters
+
+```sh
+# get the resume parameters
+RESUME_PARAMS="resume=UUID=$(findmnt / -o UUID -n) resume_offset=$(sudo filefrag -v /swapfile|awk 'NR==4{gsub(/\./,"");print $4;}') "
+
+# add them to GRUB config
+if grep resume /etc/default/grub>/dev/null; then echo -e "\nERROR: Hibernation already configured. Remove the existing configuration from /etc/default/grub and add these parameters instead:\n$RESUME_PARAMS";else sudo sed -i "s/GRUB_CMDLINE_LINUX_DEFAULT=\"/GRUB_CMDLINE_LINUX_DEFAULT=\"$RESUME_PARAMS/" /etc/default/grub;fi
+
+sudo update-grub # for Debian-based distros
+sudo grub-mkconfig -o /boot/grub/grub.cfg # for Arch
+```
+
+And... that's it!
+
+If you have problems, make sure secure boot is disabled and check your BIOS settings. NVIDIA drivers are also problematic. If you're stuck, the internet can probably help.
+
+
+Further reading:
+
+ - https://forums.linuxmint.com/viewtopic.php?t=284100
+
+ - https://forums.linuxmint.com/viewtopic.php?f=42&t=273202
+