Time Machine Backup Target
We will install Net talk to provide APF and Avahi to advertise and host on a external drive. The RPI4B firmware natively supports USB 3.0 and booting from SSD drives. Will boot from the SD card as want separate data partition. Booting from SSD is not the issue. With a 4 and latest OS it is a case of selecting the SSD drive instead of a SD card when writing the image. I want to be able to replace the data directory as required so proceeding with an separate drive. The bigger picture is to replace the XEON based device that hosts ~ 4TB for backups. There must be a RAID option with external power for the capacity but for now going with a WD 240TB Green Drive to verify its operation.
Using the ‘Green’ range as they are designed to be low power / preformance. The SSD will consume 0.60A (2.8W) and transfer over SATA III (6 Gb/s). The RPI4B is able to supply a total of 1.2 amps to its 4 USB ports if the RPi4B is powered from a 3 amp power supply and supports USB3 interface (5 Gb/s) so will be a practical match.
First ensure OS is up to date;
# sudo apt-get update && sudo apt-get upgrade -yhfsplus partition.
Here I will format an USB3 SSD hard drive using hfsplus.
# sudo apt-get install hfsutils hfsprogs -ySo this is what an fdisk -l shows when the device has the SD card to boot and OS (/dev/mmcdlk0p1/2) and ext SSD drive with single partition (/dev/sda);
Disk /dev/mmcblk0: 14.9 GiB, 15931539456 bytes, 31116288 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: dos Disk identifier: 0x74129c0a Device Boot Start End Sectors Size Id Type /dev/mmcblk0p1 8192 532479 524288 256M c W95 FAT32 (LBA) /dev/mmcblk0p2 532480 31116287 30583808 14.6G 83 Linux Disk /dev/sda: 223.6 GiB, 240065175552 bytes, 468877296 sectors Disk model: 40G2G0A-00JH30 Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: gpt Disk identifier: 7CEE32DA-6AA7-45DF-83B3-CBB22D661899 Device Start End Sectors Size Type /dev/sda1 2048 468877262 468875215 223.6G Linux filesystem
Will format as hfplus as native filesystem of Mac OS X and label accordingly;
# sudo mkfs.hfsplus /dev/sda1 -v TimeMachineCreate mount point and update permissions to allow user access;
# sudo mkdir /media/tm && sudo chmod -R 777 /media/tm && sudo chown root:users /media/tmDetermine the UUID of your USB hard drive as will be use for fstab;
$ ls -lha /dev/disk/by-uuid total 0 drwxr-xr-x 2 root root 100 Oct 7 13:13 . drwxr-xr-x 7 root root 140 Oct 7 13:13 .. lrwxrwxrwx 1 root root 15 Oct 7 13:13 7616-4FD8 -> ../../mmcblk0p1 lrwxrwxrwx 1 root root 15 Oct 7 13:13 87b585d1-84c3-486a-8f3d-77cf16f84f30 -> ../../mmcblk0p2 lrwxrwxrwx 1 root root 10 Oct 7 13:13 95042b43-d161-3363-b0a8-99291c5789d1 -> ../../sda1
then edit fstab to mount the USB hard drive on boot;
proc /proc proc defaults 0 0 PARTUUID=74129c0a-01 /boot vfat defaults 0 2 PARTUUID=74129c0a-02 / ext4 defaults,noatime 0 1 UUID=95042b43-d161-3363-b0a8-99291c5789d1 /media/tm hfsplus force,rw,user 0 0 tmpfs /var/tmp tmpfs nodev,nosuid,size=512M 0 0 tmpfs /tmp tmpfs nodev,nosuid,size=512M 0 0
Test that mounting works as expected;
$ sudo mount -a $ df -h Filesystem Size Used Avail Use% Mounted on /dev/root 15G 3.1G 11G 23% / devtmpfs 776M 0 776M 0% /dev tmpfs 937M 0 937M 0% /dev/shm tmpfs 937M 8.6M 928M 1% /run tmpfs 5.0M 8.0K 5.0M 1% /run/lock tmpfs 937M 0 937M 0% /sys/fs/cgroup tmpfs 512M 0 512M 0% /var/tmp tmpfs 512M 4.0K 512M 1% /tmp /dev/sda1 224G 184G 41G 82% /media/tm /dev/mmcblk0p1 253M 50M 204M 20% /boot tmpfs 188M 0 188M 0% /run/user/109 tmpfs 188M 0 188M 0% /run/user/1001
Netatalk
Netatalk provides Apple Filing Protocol (APF) which is Apple’s proprietary network protocol for delivering files over a network. It is Apple’s alternative to the Server Message Block (SMB) and Network File System (NFS) protocols. Version 3.x is now available from the Pi repository so can install wit apt-get .
# sudo apt-get install netatalk -y
check netatalk installed version 3.x;
# netatalk -V netatalk 3.1.12 - Netatalk AFP server service controller daemon This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. Please see the file COPYING for further information and details. netatalk has been compiled with support for these features:Zeroconf support: AvahiSpotlight support: Yesafpd: /usr/sbin/afpdcnid_metad: /usr/sbin/cnid_metadtracker manager: /usr/bin/tracker daemondbus-daemon: /usr/bin/dbus-daemonafp.conf: /etc/netatalk/afp.confdbus-session.conf: /etc/netatalk/dbus-session.confnetatalk lock file: /var/lock/netatalk
update /etc/nsswitch;
# /etc/nsswitch.conf
#
# Example configuration of GNU Name Service Switch functionality.
# If you have the `glibc-doc-reference' and `info' packages installed, try:
# `info libc "Name Service Switch"' for information about this file.
passwd: files
group: files
shadow: files
gshadow: files
hosts: files mdns4_minimal [NOTFOUND=return] dns mdns4 mdns
networks: files
protocols: db files
services: db files
ethers: db files
rpc: db files
netgroup: nisand update afp.conf;
# /etc/netatalk/afp.conf
;
; Netatalk 3.x configuration file
;
[Global]
mimic model = TimeCapsule6,106
[Time Machine]
path = /media/tm
time machine = yesAdding the following will allow support for home directories.
[Homes]
basedir regex = /homeAvahi
Avahi is a software solution enabling an easy-to-use, zero-configuration local network. It is a GNU alternative to Apple’s Bonjour software solution allowing communication between your Pi and your Mac.
At first, we will install all the prerequired elements for Avahi :
sudo apt-get install db5.1-util libgcrypt11-dev avahi-daemon libavahi-client-dev libdb5.3-dev -y
Now that Avahi is installed, we need to make sure that it starts at the boot of the Raspberry Pi. To do this, just type the following command :
sudo update-rc.d avahi-daemon defaults sudo service avahi-daemon start sudo service netatalk start
then reboot the PI.
You should be able to see the device from the Mac in finder with Time Capsule icon. There wont be home directories as yet but will be able to select and use the disk for Time Machine.
Updates.
During the process of building mirrors and testing (decided to use HW over software) managed to break the config more that once. Issues would manifest as an inability to boot and connecting a screen to the device didn’t always enable a resolution. However being able to pull the SD card and mount in another device then edit proved invaluable. So the practice is to build the boot disk on SD card, test and once stable write the SD card to the SSD drive.
# Write SD card to SSD drive. dmesg to conform device names
dmesg
sudo dd of=/dev/sdf if=/dev/sde bs=4096k status=progress
# repair dirty fs
sudo fsck /dev/sda1
# use Disk ID in fstab
sudo blkid
ls -lha /dev/disk/by-uuid
# edit fstab once mounted in another device
proc /proc proc defaults 0 0
PARTUUID=75030815-01 /boot vfat defaults 0 2
PARTUUID=75030815-02 / ext4 defaults,noatime 0 1
UUID=b878672f-e52f-451e-bd08-ebee78718437 /mnt/timemachine ext4 defaults,errors=remount-ro 0 0
tmpfs /var/tmp tmpfs nodev,nosuid,size=256M 0 0
tmpfs /tmp tmpfs nodev,nosuid,size=1024M 0 0
sudo fsck.hfsplus -f /dev/sda1
Software RAID straight forward;
sudo apt-get install mdadm -y
sudo blkid
/dev/mmcblk0p1: LABEL_FATBOOT="boot" LABEL="boot" UUID="E183-6233" BLOCK_SIZE="512" TYPE="vfat" PARTUUID="75030815-01"
/dev/mmcblk0p2: LABEL="rootfs" UUID="1232a209-2596-48f0-a078-731d10b918ad" BLOCK_SIZE="4096" TYPE="ext4" PARTUUID="75030815-02"
/dev/sdb1: LABEL="4TB02" UUID="6ec671a5-b278-4c1f-b246-2c5a3b0327c2" BLOCK_SIZE="4096" TYPE="ext4" PARTUUID="67924807-e66f-3b47-9655-c62f6c2a4896"
/dev/sda1: LABEL="4TB01" UUID="74bd0e3c-332b-4b9a-a738-403e06a2ffdf" BLOCK_SIZE="4096" TYPE="ext4" PARTUUID="47d25b7e-39b9-2b49-adc8-61282cc279fd"
sudo mdadm --create --verbose /dev/md0 --level=mirror --raid-devices=2 /dev/sda1 /dev/sdb1
mdadm --detail --scan
sudo -i
mdadm --detail --scan >> /etc/mdadm/mdadm.conf
mkfs.ext4 -v -m .1 -b 4096 -E stride=32,stripe-width=64 /dev/md0
# Add to /etc/fstab
UUID=5af30b6a-2ce2-45ac-92ca-f4559c02c97e /mnt/raid0 ext4 defaults 0 0
