How to configure Borg client on macOS using command-line
Requirements
- Borg server (self-hosted or cloud-based such as BorgBase or rsync.net)
- Computer running macOS Mojave or Catalina
Caveats
- When copy/pasting commands that start with
$
, strip out$
as this character is not part of the command - When copy/pasting commands that start with
cat << "EOF"
, select all lines at once (fromcat << "EOF"
toEOF
inclusively) as they are part of the same (single) command
Setup guide
Heads-up: steps 1 to 4 are only required if using BorgBase or rsync.net (don’t forget to enable 2FA).
Step 1: create borg
SSH key pair (if using BorgBase or rsync.net)
When asked for file in which to save key, enter borg
.
When asked for passphrase, use output from openssl rand -base64 24
(and store passphrase in password manager).
Use borg.pub
public key when configuring Borg server.
$ mkdir -p ~/.ssh
$ cd ~/.ssh
$ ssh-keygen -t rsa -C "borg"
Generating public/private rsa key pair.
Enter file in which to save the key (/Users/sunknudsen/.ssh/id_rsa): borg
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in borg.
Your public key has been saved in borg.pub.
The key fingerprint is:
SHA256:b4YxePgBjP9hB/wPFz7MkzM5fDYEBtbtOBd7kxRTicY borg
The key's randomart image is:
+---[RSA 3072]----+
| oo+..o=|
| o . . ..Eoo.|
| . o o oooo.|
| . + o =o=+o.|
| + S + #o+..|
| = O + O . |
| + + . |
| o |
| |
+----[SHA256]-----+
$ cat borg.pub
ssh-rsa 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 borg
Step 2: create borg-append-only
SSH key pair (if using BorgBase or rsync.net)
When asked for file in which to save key, enter borg-append-only
.
When asked for passphrase, leave field empty for no passphrase (this public key will be used for append-only operations).
Use borg-append-only.pub
public key when configuring Borg server.
$ ssh-keygen -t rsa -C "borg-append-only"
Generating public/private rsa key pair.
Enter file in which to save the key (/Users/sunknudsen/.ssh/id_rsa): borg-append-only
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in borg-append-only.
Your public key has been saved in borg-append-only.pub.
The key fingerprint is:
SHA256:xR8BvPMujEM955VubA/TWVlqt/Nt2INNX4UIw3wtssw borg-append-only
The key's randomart image is:
+---[RSA 3072]----+
| +.... |
| .B o.. |
| ooB.o ..|
| .E.....+|
| S. o. oo+|
| . o o.o+=|
| . o = +**+|
| o o o.*=B|
| . . o o=|
+----[SHA256]-----+
$ cat borg-append-only.pub
ssh-rsa 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 borg-append-only
Step 3: configure SSH keys and create repo (if using BorgBase)
Configure SSH keys
Go to SSH Keys and add borg.pub
and borg-append-only.pub
keys.
Create repo
Go to Repositories and add repository.
Step 4: generate and upload authorized_keys
file (if using rsync.net)
Set temporary environment variable
BORG_STORAGE_QUOTA="500G"
Generate authorized_keys
file
Replace 18434
with rsync.net username.
cat << EOF > ~/Desktop/authorized_keys
command="borg1 serve --restrict-to-repository /data1/home/18434/backup --storage-quota $BORG_STORAGE_QUOTA",restrict $(cat ~/.ssh/borg.pub)
command="borg1 serve --append-only --restrict-to-repository /data1/home/18434/backup --storage-quota $BORG_STORAGE_QUOTA",restrict $(cat ~/.ssh/borg-append-only.pub)
EOF
Upload authorized_keys
file
scp ~/Desktop/authorized_keys 18434@ch-s011.rsync.net:.ssh/authorized_keys
Step 5: install Homebrew
/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install.sh)"
Step 6: disable Homebrew analytics
brew analytics off
Step 7: install FUSE for macOS, Borg and Borg Wrapper
Heads-up: when installing Borg using
brew install borgbackup
, one can no longer runbrew mount
(see issue #5522) so I created a tap that includes a patched version of borgbackup called borgbackup-fuse.
Heads-up: if
brew install --cask osxfuse
fails, trybrew cask install osxfuse
(see #9382).
brew install --cask osxfuse
brew install borgbackup/tap/borgbackup-fuse
brew install --cask sunknudsen/tap/borg-wrapper
Step 8: configure Borg
Generate Borg passphrase using openssl
and add passphrase to “Keychain Access”
security add-generic-password -D secret -U -a $USER -s borg-passphrase -w $(openssl rand -base64 24)
Initialize Borg repo
Replace borg@185.112.147.115:backup
with self-hosted or cloud-based repo.
$ export BORG_PASSCOMMAND="security find-generic-password -a $USER -s borg-passphrase -w"
$ export BORG_RSH="ssh -i ~/.ssh/borg"
$ borg init --encryption=keyfile-blake2 "borg@185.112.147.115:backup"
Enter passphrase for key '/Users/sunknudsen/.ssh/borg':
By default repositories initialized with this version will produce security
errors if written to with an older version (up to and including Borg 1.0.8).
If you want to use these older versions, you can disable the check by running:
borg upgrade --disable-tam ssh://borg@185.112.147.115/./backup
See https://borgbackup.readthedocs.io/en/stable/changes.html#pre-1-0-9-manifest-spoofing-vulnerability for details about the security implications.
IMPORTANT: you will need both KEY AND PASSPHRASE to access this repo!
Use "borg key export" to export the key, optionally in printable format.
Write down the passphrase. Store both at safe place(s).
Backup ~/.config/borg
and ~/Library/Keychains
folders
Heads-up: both key (stored in
~/.config/borg
) and passphrase (stored in~/Library/Keychains
) are required to decrypt backup.
Step 9: set temporary environment variables
Replace borg@185.112.147.115:backup
with self-hosted or cloud-based repo and set backup name.
BORG_REPO="borg@185.112.147.115:backup"
BACKUP_NAME="$USER-macbook-pro"
Step 10: create /usr/local/bin/borg-backup.sh
script
cat << EOF > /usr/local/bin/borg-backup.sh
#! /bin/sh
set -e
repo="$BORG_REPO"
prefix="$BACKUP_NAME-"
export BORG_PASSCOMMAND="security find-generic-password -a $USER -s borg-passphrase -w"
export BORG_RSH="ssh -i ~/.ssh/borg-append-only"
borg create \\
--filter "AME" \\
--list \\
--stats \\
--verbose \\
"\$repo::\$prefix{now:%F-%H%M%S}" \\
"/Users/$USER/.ssh" \\
"/Users/$USER/Library/Keychains"
printf "%s\n" "Done"
EOF
chmod +x /usr/local/bin/borg-backup.sh
Step 11: edit /usr/local/bin/borg-backup.sh
script
vi /usr/local/bin/borg-backup.sh
Step 12: create /usr/local/bin/borg-list.sh
script
cat << EOF > /usr/local/bin/borg-list.sh
#! /bin/sh
set -e
prefix="$BACKUP_NAME-"
repo="$BORG_REPO"
export BORG_PASSCOMMAND="security find-generic-password -a $USER -s borg-passphrase -w"
export BORG_RSH="ssh -i ~/.ssh/borg-append-only"
borg list --prefix "\$prefix" "\$repo"
printf "%s\n" "Done"
EOF
chmod +x /usr/local/bin/borg-list.sh
Step 13: create /usr/local/bin/borg-check.sh
script
cat << EOF > /usr/local/bin/borg-check.sh
#! /bin/sh
set -e
prefix="$BACKUP_NAME-"
repo="$BORG_REPO"
export BORG_PASSCOMMAND="security find-generic-password -a $USER -s borg-passphrase -w"
export BORG_RSH="ssh -i ~/.ssh/borg-append-only"
borg check --prefix "\$prefix" "\$repo"
printf "%s\n" "Done"
EOF
chmod +x /usr/local/bin/borg-check.sh
Step 14: create /usr/local/bin/borg-restore.sh
script
cat << EOF > /usr/local/bin/borg-restore.sh
#! /bin/sh
set -e
function umount()
{
if [ -d "\$mount_point" ]; then
borg umount \$mount_point
fi
}
trap umount ERR INT
mount_point="\${TMPDIR}borg"
prefix="$BACKUP_NAME-"
repo="$BORG_REPO"
mkdir -p \$mount_point
export BORG_PASSCOMMAND="security find-generic-password -a $USER -s borg-passphrase -w"
export BORG_RSH="ssh -i ~/.ssh/borg-append-only"
borg mount --prefix "\$prefix" "\$repo" "\$mount_point"
open \$mount_point
printf "Restore data and press enter"
read -r answer
umount
printf "%s\n" "Done"
EOF
chmod +x /usr/local/bin/borg-restore.sh
Step 15: create /usr/local/bin/borg-prune.sh
script
cat << EOF > /usr/local/bin/borg-prune.sh
#! /bin/sh
set -e
prefix="$BACKUP_NAME-"
repo="$BORG_REPO"
export BORG_PASSCOMMAND="security find-generic-password -a $USER -s borg-passphrase -w"
export BORG_RSH="ssh -i ~/.ssh/borg"
borg prune --keep-hourly 24 --keep-daily 31 --keep-weekly 52 --keep-monthly -1 --list --prefix "\$prefix" --stats "\$repo"
printf "%s\n" "Done"
EOF
chmod +x /usr/local/bin/borg-prune.sh
Step 16: create /usr/local/var/log
folder
mkdir -p /usr/local/var/log
Step 17: run “Borg Wrapper”
open /Applications/Borg\ Wrapper.app
Heads-up: given “Borg Wrapper” is developed outside the Apple Developer Program, macOS prevents opening the app without explicit user consent (granted by clicking “Open Anyway” in “System Preferences” / “Privacy & Security”).
Backup completed
👍
Step 18: schedule backup every hour using launchd
mkdir -p ~/Library/LaunchAgents
cat << EOF > ~/Library/LaunchAgents/local.borg-wrapper.plist
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>Label</key>
<string>Borg Wrapper.app</string>
<key>ProgramArguments</key>
<array>
<string>open</string>
<string>/Applications/Borg Wrapper.app</string>
</array>
<key>RunAtLoad</key>
<false/>
<key>StartCalendarInterval</key>
<dict>
<key>Minute</key>
<integer>0</integer>
</dict>
</dict>
</plist>
EOF
launchctl load ~/Library/LaunchAgents/local.borg-wrapper.plist
👍
Usage guide
Backup
$ borg-backup.sh
Creating archive at "borg@185.112.147.115:backup::sunknudsen-macbook-pro-{now:%F-%H%M%S}"
A /Users/sunknudsen/Library/Keychains/4FD89B1C-70AF-58EC-8026-35E97A08F9FE/keychain-2.db-wal
Remote: Storage quota: 314.36 kB out of 10.00 GB used.
Remote: Storage quota: 318.04 kB out of 10.00 GB used.
------------------------------------------------------------------------------
Archive name: sunknudsen-macbook-pro-2020-12-02-081439
Archive fingerprint: 781c5ca9dac166264250bdbe2c87aa1f9fb5f817cafd66d1e720dfdaa443f625
Time (start): Wed, 2020-12-02 08:14:41
Time (end): Wed, 2020-12-02 08:14:42
Duration: 0.29 seconds
Number of files: 28
Utilization of max. archive size: 0%
------------------------------------------------------------------------------
Original size Compressed size Deduplicated size
This archive: 6.81 MB 312.77 kB 3.54 kB
All archives: 13.62 MB 625.53 kB 316.18 kB
Unique chunks Total chunks
Chunk index: 29 56
------------------------------------------------------------------------------
Done
Done
👍
List
$ borg-list.sh
sunknudsen-macbook-pro-2020-12-02-081338 Wed, 2020-12-02 08:13:41 [c01b3400ec076adb993a2c268cd48810da9acc122614cdc4c87e00075464c1ee]
sunknudsen-macbook-pro-2020-12-02-081439 Wed, 2020-12-02 08:14:41 [781c5ca9dac166264250bdbe2c87aa1f9fb5f817cafd66d1e720dfdaa443f625]
Done
Done
👍
Check
$ borg-check.sh
Done
Done
👍
Restore
$ borg-restore.sh
mount_osxfuse: the file system is not available (1)
umount: /var/folders/dl/mbmsd2m51nb8dvhmtz114j8w0000gn/T/borg: not currently mounted
Heads-up: given “FUSE for macOS” is a third-party extension, macOS prevents using the extension without explicit user consent (granted by clicking “Allow” in “System Preferences” / “Privacy & Security”).
$ borg-restore.sh
Restore data and press enter
Done
Done
👍
Prune
$ borg-prune.sh
Enter passphrase for key '/Users/sunknudsen/.ssh/borg':
Keeping archive: sunknudsen-macbook-pro-2020-12-02-081439 Wed, 2020-12-02 08:14:41 [781c5ca9dac166264250bdbe2c87aa1f9fb5f817cafd66d1e720dfdaa443f625]
Pruning archive: sunknudsen-macbook-pro-2020-12-02-081338 Wed, 2020-12-02 08:13:41 [c01b3400ec076adb993a2c268cd48810da9acc122614cdc4c87e00075464c1ee] (1/1)
------------------------------------------------------------------------------
Original size Compressed size Deduplicated size
Deleted data: -6.81 MB -312.76 kB -3.52 kB
All archives: 6.81 MB 312.77 kB 312.65 kB
Unique chunks Total chunks
Chunk index: 27 28
------------------------------------------------------------------------------
Done
Done
👍