configure-fast-vm

#!/bin/sh
config_file="/etc/fast-vm.conf"

## terminal colors
c_red=$(tput setaf 1)
c_yellow=$(tput setaf 3)
c_green=$(tput setaf 2)
c_cyan=$(tput setaf 6)
c_normal=$(tput sgr0)
## common outputs
o_err="[${c_red}err${c_normal}]"
o_wrn="[${c_yellow}wrn${c_normal}]"
o_inf="[${c_cyan}inf${c_normal}]"
o_ok="[${c_green}ok${c_normal}]"

# load defaults and old configuration if exists
if [ -f /usr/share/fast-vm/fast-vm.conf.defaults ]; then
	. /usr/share/fast-vm/fast-vm.conf.defaults
fi
if [ -f "$config_file" ]; then
	. $config_file
else
	touch $config_file
fi

ask_question () {
	question="$1"
	default_value="$2"
	config_variable="$3"

	# lets get meaningfull answer from user
	success=0
	while [ "$success" -eq 0 ];
	do
		printf "[?] $question \n[$default_value]: "
		read answer
		if [ -z "$default_value" ] && [ -z "$answer" ]; then
			printf "$o_err You must provide value\n"
		else
			success=1
		fi
		echo
	done

	# and write the output into configuration file
	sed -i "/^$config_variable=/d" $config_file
	if [ -z "$answer" ]; then
		echo "$config_variable=$default_value" >> $config_file
	else
		echo "$config_variable=$answer" >> $config_file
	fi
	. $config_file
}

test_appliance () {
	tmp_appliance_test=$(mktemp)
	printf "$o_inf Running appliance test (libguestfs-test-tool)...\n"
	if LIBGUESTFS_PATH=/var/lib/fast-vm/appliance libguestfs-test-tool >"$tmp_appliance_test" 2>&1; then
		printf "$o_inf Appliance test looks OK\n"
		rm -f "$tmp_appliance_test"
		return 0
	else
		printf "$o_err Appliance test failed with error, check the '$tmp_appliance_test' file for details\n"
		return 1
	fi
}

printf "$o_inf ==>> fast-vm configuration script\nYou can run this script repeatedly and interrupt it with ctrl+c.\nScript will always recheck all configuration options. fast-vm system configuration will be saved in /etc/fast-vm.conf.\n\n"

## check if we can connect to libvirt and if not, inform the user that it is needed
virsh_test=$(virsh --connect qemu:///system exit >/dev/null 2>&1)
if [ "$?" != '0' ]; then
	printf "$o_err libvirt daemon is not running or we cannot connect to it.\nEnsure that libvirt service is running and that you can connect to it using command 'virsh --connect qemu:///system' and then re-run this configuration script.\n"
	exit 1
fi

success=0
while [ "$success" -eq 0 ];
do
	if command -v systemctl >/dev/null && command -v losetup >/dev/null && command -v truncate >/dev/null; then
		printf "$o_inf (Optional) On systemd systems fast-vm can automatically setup loop device to provide storage for fast-vm VG. \n This option is intended for uses where no VFree is available on system. \n"
		printf "[?] Would you like to start the fast-vm-loop-device.service? (y/n) [n] "
		read answer
		if [ "$answer" = "y" ]; then
			if [ ! -f "/var/lib/fast-vm/loop/device.img" ]; then
				printf "[?] Loop device (sparse file) size in GB: [51] "
				read loopdev_size
				if [ -z "$loopdev_size" ]; then loopdev_size='51'; fi
			        if [ ! -d "/var/lib/fast-vm/loop" ]; then mkdir -p /var/lib/fast-vm/loop; fi
				printf "$o_inf Creating ${loopdev_size}GB file /var/lib/fast-vm/loop/device.img with VG fastvm-loopdevice.\n"
				truncate -s "${loopdev_size}G" /var/lib/fast-vm/loop/device.img
                        fi
			printf "$o_inf Enabling on boot and starting now the 'fast-vm-loop-device.service' ...\n"
			systemctl enable --now fast-vm-loop-device.service
			vgcreate fastvm-loopdevice /dev/loop100
			printf "$o_inf You should see now the new VG named 'fastvm-loopdevice'.\n This VG can be used for fast-vm storage in next steps. \n\n"
		else
			printf "$o_inf If it turns out you don't have any VFree in system, \n you can re-run config and choose to start the 'fast-vm-loop-device.service'. \n\n"
		fi
	fi

	available_vgs=$(vgs -o vg_name,vg_attr,vg_size,vg_free)
	ask_question "VG for LVM thin pool\n fast-vm is using LVM thin LV to store VM images and data.\n Available VGs on your system are: \n $available_vgs\n ====== \n Choose the VG with sufficient VFree space for fast-vm use (at least 10GB recommended).\n If you lack sufficient VFree space you can use the 'fastvm-loopdevice'. \n ====== \n On which existing VG should be this thin LV?" "$THINPOOL_VG" "THINPOOL_VG"
	ask_question "LVM thin pool name\n Name the thin LV on which data would be stored.\n NOTE: This can be both 'name of existing thinpool LV' or 'name for a new one'.\n If LV with this name doesn't exists, it will get created by this setup." "$THINPOOL_LV" "THINPOOL_LV"

	lvdisplay "$THINPOOL_VG/$THINPOOL_LV" >/dev/null 2>&1
	if [ ! "$?" -eq "0" ]; then
		ask_question "LVM thin pool size\n You can use units understood by LVM like M,G,T.\n NOTE: This applies only when thin LV doesn't exists yet." "$THINPOOL_SIZE" "THINPOOL_SIZE"
	fi
	ask_question "VM name prefix in libvirt\n Prefix is used in VM names and VM drive names." "$VM_PREFIX" "VM_PREFIX"

	ask_question "Users that want to use fast-vm must be members of following group.\n WARNING: if this group is different from 'libvirt' you would have to adjust libvirt configuration.\n Please check the fast-vm.conf(5) if setting this to something else than 'libvirt'." "$FASTVM_GROUP" "FASTVM_GROUP"
	if [ "$FASTVM_GROUP" != "libvirt" ]; then
		printf "$o_wrn You are using non-default group for FASTVM_GROUP.\n Please check the fast-vm.conf(5) on how to configure libvirtd for this to work properly.\n\n"
	fi

	ask_question "Libvirt network (bridge) name\n This configuration will create a libvirt \n network with this name providing NAT for VMs." "$LIBVIRT_NETWORK" "LIBVIRT_NETWORK"
	ask_question "Libvirt subnet number (192.168.XX.0/24)" "$SUBNET_NUMBER" "SUBNET_NUMBER"

	ask_question "Only 'root' and 'owner' of VM should be able to delete VM through fast-vm?\n \"yes\" - only 'root' and 'owner' can delete VM\n \"no\" - anyone allowed to use fast-vm can delete VM (default in versions =< 0.9)" "$FASTVM_OWNER_ONLY_DELETE" "FASTVM_OWNER_ONLY_DELETE"

	ask_question "Generate or Import libguestfs appliance used by hack files for this system? ('Generate' will generate appliance localy, while 'import' allows to import pre-build Fedora appliance from Internet.\nFASTVM_APPLIANCE_URL=$FASTVM_APPLIANCE_URL\nSome fast-vm images may require the Fedora appliance otherwise their hack files fails.)" "$FASTVM_APPLIANCE" "FASTVM_APPLIANCE"

	ask_question "Default password for fast-vm keydist operation (use 'none' to disable this feature)" "$FASTVM_KEYDIST_PASSWORD" "FASTVM_KEYDIST_PASSWORD"
	if [ "$FASTVM_KEYDIST_PASSWORD" = 'none' ]; then sed -i '/^FASTVM_KEYDIST_PASSWORD=/g' "$config_file"; fi

	## reload the configuration file and check the system for changes
	. $config_file

	# redefine the sudoers file
	sed -i -e "s/^\%[^ ]* \(.* \/usr\/libexec\/fast-vm-helper\.sh\)$/\%${FASTVM_GROUP} \1/" /etc/sudoers.d/fast-vm-sudoers >/dev/null 2>&1

	# LVM VG check
	vgdisplay "$THINPOOL_VG"  >/dev/null 2>&1
	if [ ! "$?" -eq '0' ]; then
		printf "$o_err VG '$THINPOOL_VG' not found\n"
		continue
	fi

	# LVM thinpool LV check
	lvdisplay "$THINPOOL_VG/$THINPOOL_LV" >/dev/null 2>&1
	if [ ! "$?" -eq "0" ]; then
		printf "$o_wrn LV '$THINPOOL_VG/$THINPOOL_LV' not found\n"
		echo "Following commands would be executed to create thin pool:"
		echo "  lvcreate -n $THINPOOL_LV -L $THINPOOL_SIZE $THINPOOL_VG"
		echo "  lvconvert --type thin-pool $THINPOOL_VG/$THINPOOL_LV"
		printf "[?] Create now? (y/n) "
		read answer
		if [ "$answer" = "y" ]; then
			printf "$o_inf Creating ...\n"
			## create thin pool
			lvcreate -n "$THINPOOL_LV" -L "$THINPOOL_SIZE" "$THINPOOL_VG"
			if [ ! "$?" -eq "0" ]; then
				printf "$o_err Error while creating LV for thin pool, aborting\n"
				exit 1
			fi
			lvconvert --type thin-pool "$THINPOOL_VG/$THINPOOL_LV"
			if [ ! "$?" -eq "0" ]; then
				printf "$o_err Error while converting LV into thin pool, aborting\n"
				exit 1
			fi
			printf "$o_ok LVM thinpool successfuly created\n"
		else
			printf "$o_wrn fast-vm will not work without thinpool LV!\n"
		fi
	fi

	# check if the LV is a thinpool
	is_thin_pool=$(lvdisplay "/dev/$THINPOOL_VG/$THINPOOL_LV" 2>/dev/null|grep 'LV Pool'|wc -l)
	if [ ! "$is_thin_pool" -eq "2" ]; then
		printf "$o_err LV /dev/$THINPOOL_VG/$THINPOOL_LV is not a thin pool. To create a thinpool for fast-vm delete this LV a run the configuration again\n"
		exit 1
	fi

	# check for the libvirt network
	virsh --connect qemu:///system net-info "$LIBVIRT_NETWORK" >/dev/null 2>&1
	if [ ! "$?" -eq "0" ]; then
		printf "[?] Network $LIBVIRT_NETWORK is not defined in libvirt, define now? (y/n) "
		read answer
		if [ "$answer" = "y" ]; then
			printf "$o_inf Creating ...\n"
			tmp_file=$(mktemp --suffix=.xml)
			sed -e "s/NET_NAME/$LIBVIRT_NETWORK/g; s/SUBNET_NUMBER/$SUBNET_NUMBER/g" /usr/share/fast-vm/fast-vm-network.xml > "$tmp_file"
			virsh --connect qemu:///system net-define "$tmp_file"
			if [ ! "$?" -eq "0" ]; then
				printf "$o_err Error creating libvirt network, aborting\n"
				exit 1
			fi
			virsh --connect qemu:///system net-autostart "$LIBVIRT_NETWORK"
			if [ ! "$?" -eq "0" ]; then
				printf "$o_err Error marking libvirt network as autostarted, aborting\n"
				exit 1
			fi
			virsh --connect qemu:///system net-start "$LIBVIRT_NETWORK"
			if [ ! "$?" -eq "0" ]; then
				printf "$o_err Error starting libvirt network, aborting\n"
				exit 1
			fi
			printf "$o_inf fast-vm libvirt network created and autostarted\n"
		else
			printf "$o_wrn fast-vm will not work without libvirt network!\n"
		fi
	fi

	is_subnet_number=$(virsh --connect qemu:///system net-dumpxml "$LIBVIRT_NETWORK" 2>/dev/null|grep 'ip address'|cut -d. -f3)
	if [ "$is_subnet_number" != "$SUBNET_NUMBER" ];then
		printf "$o_err Libvirt network subnet is different from one provided in fast-vm configuration. Fix fast-vm configuration or libvirt network configuration\n"
		exit 1
	fi

	if [ -n "$FASTVM_NOTES_DIR" ] && [ "$(whoami)" = "root" ]; then
		printf "[!] Configuration option FASTVM_NOTES_DIR is deprecated from fast-vm version 1.8.\n"
		printf "    If you need to convert notes from old format then use configure-fast-vm from version 1.7.\n"
		if [ ! -d "$FASTVM_NOTES_DIR" ]; then
			printf "[i] Please remove FASTVM_NOTES_DIR from /etc/fast-vm.conf\n"
			printf "    as directory ($FASTVM_NOTES_DIR) defined in it doesn't exist.\n"
		fi
	fi

	if test_appliance; then
		printf "$o_inf Current appliance looks OK. No changes needed. If you wanna replace it, then remove /var/lib/fast-vm/appliance directory\n"
	else
		case "$FASTVM_APPLIANCE" in
		import)
			printf "$o_inf Downloading appliance from $FASTVM_APPLIANCE_URL\n"
			tmp_file=$(mktemp)
			curl "$FASTVM_APPLIANCE_URL" > "$tmp_file"
			printf "$o_inf Extracting file into /var/lib/fast-vm\n"
			if [ ! -d "/var/lib/fast-vm" ]; then mkdir -p /var/lib/fast-vm; fi
			tar xvf "$tmp_file" -C /var/lib/fast-vm
			rm -f "$tmp_file"
			test_appliance
			;;
		generate)
			if command -v libguestfs-make-fixed-appliance >/dev/null 2>&1; then
				printf "$o_inf Generating locally new appliance (this can take around minutes)\n"
				libguestfs-make-fixed-appliance /var/lib/fast-vm/appliance
				test_appliance
			else
				printf "$o_err Command 'libguestfs-make-fixed-appliance' not found.\n"
				printf "$o_err Try installing package containing it (usually 'libguestfs-devel') or\n"
				printf "$o_err choose to 'import' appliance instead of generating it.\n"
			fi
			;;
		skip)
			printf "$o_wrn Skipping appliance import/generation\n"
			;;
		*)
			printf "$o_err Unrecognized option. Use one of 'import', 'generate' or 'skip'.\n"
			;;
		esac

	fi

	printf "$o_ok fast-vm configured\n"
	success=1
done