#!/bin/bash

# Cherryservers.com block storage script for attaching and detaching volume on Linux

function print_usage() {
    echo "Usage: $(basename $0) [-h] -v <vlan id> -z <vlan ip> -d <portal ip> -i <initiator name> -e -q"
    echo
    echo "  -i  initiator name"
    echo "  -d  discovery IP address"
    echo "  -v  VLAN"
    echo "  -z  VLAN IP address"
    echo "  -e  attach volume"
    echo "  -q  detach volume"
    echo
}

shopt -s nocasematch

template=$(mktemp)
systemctl=0
systemctl 2>/dev/null |grep -q '\-\.mount'
[[ $? -eq 0 ]] && systemctl=1
attach=no
detach=no

while getopts ":a:cheqwti:P:v:d:f:s:z:n:" opt; do
    case $opt in
        a) ipaddr=$OPTARG ;;
        h) help=yes ;;
        i) initiator=$OPTARG ;;
        d) discovery_ip_1=$OPTARG ;;
        z) vlan_ip_1=$OPTARG ;;
        v) vlan_id=$OPTARG ;;
        e) attach=yes ;;
        q) detach=yes ;;
       \?)
           echo "Invalid option: -$OPTARG" >&2
           print_usage >&2
           exit 1
           ;;
    esac
done

if [[ "$help" == "yes" ]]; then
    print_usage
    exit 0;
fi

if [[ "$attach" == "yes" ]]; then

    if [[ -z "$vlan_ip_1" ]]; then
        echo "No vlan IP address provided!"
        exit 1;
    fi

    if [[ -z "$vlan_id" ]]; then
        echo "No vlan ID provided!"
        exit 1;
    fi

    if [[ -z "$discovery_ip_1" ]]; then
        echo "No discovery IP provided!"
        exit 1;
    fi

    if [[ -z "$initiator" ]]; then
        echo "No initiator name provided!"
        exit 1;
    fi

elif [[ "$detach" == "yes" ]]; then

    if [[ -z "$vlan_ip_1" ]]; then
        echo "No vlan IP address provided!"
        exit 1;
    fi

    if [[ -z "$discovery_ip_1" ]]; then
        echo "No discovery IP provided!"
        exit 1;
    fi

else
    echo "Either attach or detach option is required!"
    print_usage
    exit 0;
fi

function make_network_config_template() {

    local vlan_interface=$1
    local vlan_id=$2
    local vlan_ip_2=$3

    if [[ "$dist_name" == "ubuntu" ]] && [[ "$dist_vers" =~ 18|20|22 ]]; then
        cat > $template << EOF
network:
    version: 2
    $([[ "$dist_vers" =~ 20|22 ]] && { echo "renderer: NetworkManager"; })
    vlans:
        $vlan_interface.$vlan_id:
            addresses:
            - $vlan_ip_2/24
            id: $vlan_id
            link: $vlan_interface
            nameservers:
                addresses:
                - 46.166.166.46
                - 5.199.160.160
                search:
                - localdomain
EOF
    elif [[ "$dist_name" == "ubuntu" ]] || [[ "$dist_name" == "debian" ]]; then
        cat > $template << EOF
auto $vlan_interface.$vlan_id
iface $vlan_interface.$vlan_id inet static
    address $vlan_ip_2/24
    mtu 1500
    vlan-raw-device $vlan_interface
    vlan_id $vlan_id
EOF
    elif [[ "$dist_name" == "centos" ]] || [[ "$dist_name" == "almalinux" ]]; then
        cat > $template << EOF
BOOTPROTO=none
DEVICE=$vlan_interface.$vlan_id:1
IPADDR=$vlan_ip_2
MTU=1500
NETMASK=255.255.255.0
NM_CONTROLLED=no
ONBOOT=yes
PHYSDEV=$vlan_interface
USERCTL=no
VLAN=yes
EOF
    elif [[ "$dist_name" == "opensuse" ]]; then
        cat > $template << EOF
IPADDR_1=$vlan_ip_2
NETMASK_1=255.255.255.0
EOF
    else
        echo "Unknown distribution."
        exit 1
    fi

}

function check_if_secondary_vlan_ip_is_up() {

    local vlan_ip_2=$1
    ip -4 a|grep -qwo $vlan_ip_2; [[ $? -eq 0 ]] && { return 0; } || { return 1; }
}

function detect_distribution() {

    echo -e "........";
    echo "Detect distribution:"
    if [[ -f /etc/os-release ]]; then
        t_var=$(grep -Po '^ID=["]*\K(\w+)|^VERSION_ID=["]*\K(\w+)' /etc/os-release 2>/dev/null|sort -r|tr '\n' ' ')

        dist_name=$(cut -d ' ' -f1 <<< $t_var)
        dist_vers=$(cut -d ' ' -f2 <<< $t_var)
    elif [[ -f /etc/centos-release ]]; then
        dist_name="centos"
        dist_vers=$(grep -Po 'release \K(\d)' /etc/centos-release)
    fi

    echo -e "\tDist: $dist_name\tVer: $dist_vers"
    echo "Detect distribution. Done"

}

function restart_network() {

    local vlan_interface=$1
    local vlan_id=$2

    # Restart network
    if [[ "$dist_name" == "ubuntu" ]] && [[ "$dist_vers" =~ 18|20 ]]; then
        netplan apply
    elif [[ "$dist_name" == "ubuntu" ]] && [[ "$dist_vers" == "22" ]]; then
        netplan apply && sleep 3 \
        && netplan apply && systemctl start NetworkManager \
        && nmcli networking off && nmcli networking on
    elif [[ "$dist_name" == "ubuntu" ]] && [[ "$dist_vers" == "14" ]]; then
        ifdown $vlan_interface.$vlan_id && ifup $vlan_interface.$vlan_id
    elif [[ "$dist_name" == "centos" ]] && [[ "$dist_vers" != "8" ]]; then
        ip addr flush $vlan_interface.$vlan_id
        [[ "$systemctl" -eq 1 ]] && systemctl restart network || service network restart
    elif [[ "$dist_name" == "centos" ]] && [[ "$dist_vers" == "8" ]]; then
        ip addr flush $vlan_interface.$vlan_id
        ifdown $vlan_interface.$vlan_id && ifup $vlan_interface.$vlan_id
    elif [[ "$dist_name" == "almalinux" ]] && [[ "$dist_vers" == "8" ]]; then
        ip addr flush $vlan_interface.$vlan_id
        ifdown $vlan_interface.$vlan_id && ifup $vlan_interface.$vlan_id
    elif [[ "$dist_name" == "almalinux" ]] && [[ "$dist_vers" == "9" ]]; then
        systemctl restart NetworkManager
    elif [[ "$dist_name" == "opensuse" ]]; then
        [[ "$systemctl" -eq 1 ]] && systemctl restart network || service network restart
    else
        [[ "$systemctl" -eq 1 ]] && systemctl restart networking
    fi

    sleep 20;
}

function reboot_iscsid() {

    # Restart iscsid
    echo -e "........"
    echo "Reboot iscsid service:"

    if [[ "$dist_name" == "ubuntu" ]] || [[ "$dist_name" == "debian" ]]; then

        if [[ "$dist_name" == "ubuntu" ]] && [[ "$dist_vers" != "14" ]]; then
            [[ "$systemctl" -eq 1 ]] && systemctl restart iscsid || service iscsid restart
        elif [[ "$dist_name" == "debian" ]] && [[ "$dist_vers" != "8" ]]; then
            [[ "$systemctl" -eq 1 ]] && systemctl restart iscsid || service iscsid restart
        elif [[ "$dist_name" == "ubuntu" ]] && [[ "$dist_vers" == "14" ]]; then
            [[ "$systemctl" -eq 1 ]] && systemctl restart open-iscsi || service open-iscsi restart
        elif [[ "$dist_name" == "debian" ]] && [[ "$dist_vers" == "8" ]]; then
            [[ "$systemctl" -eq 1 ]] && systemctl restart open-iscsi || service open-iscsi restart
        fi
    elif
        [[ "$dist_name" == "centos" ]] || [[ "$dist_name" == "almalinux" ]]; then
            [[ "$systemctl" -eq 1 ]] && systemctl restart iscsid || service iscsid restart
    elif
        [[ "$dist_name" == "opensuse" ]]; then
            [[ "$systemctl" -eq 1 ]] && systemctl restart iscsid || service iscsid restart
    else
        echo -e "Unknown distribution!"
    fi

    echo "Reboot iscsid service. Done."
}

function calculate_ips() {

    local vlan_ip_1=$1
    local discovery_ip_1=$2

    # Get secondary vlan and discovery IP addresses
    if [[ "$vlan_ip_1" =~ "10.160." ]] || [[ "$vlan_ip_1" =~ "10.16ą." ]]; then
        vlan_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $vlan_ip_1)
        discovery_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $discovery_ip_1)

    elif [[ "$vlan_ip_1" =~ "10.162." ]] || [[ "$vlan_ip_1" =~ "10.163." ]] || [[ "$vlan_ip_1" =~ "10.164." ]]; then
        vlan_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $vlan_ip_1)
        discovery_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $discovery_ip_1)

    elif [[ "$vlan_ip_1" =~ "10.165." ]] || [[ "$vlan_ip_1" =~ "10.166." ]] || [[ "$vlan_ip_1" =~ "10.167." ]]; then
        vlan_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $vlan_ip_1)
        discovery_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $discovery_ip_1)

    elif [[ "$vlan_ip_1" =~ "10.168." ]] || [[ "$vlan_ip_1" =~ "10.169." ]] || [[ "$vlan_ip_1" =~ "10.170." ]]; then
        vlan_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $vlan_ip_1)
        discovery_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $discovery_ip_1)

    elif [[ "$vlan_ip_1" =~ "10.171." ]] || [[ "$vlan_ip_1" =~ "10.172." ]] || [[ "$vlan_ip_1" =~ "10.173." ]]; then
        vlan_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $vlan_ip_1)
        discovery_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $discovery_ip_1)

    elif [[ "$vlan_ip_1" =~ "10.174." ]] || [[ "$vlan_ip_1" =~ "10.175." ]] || [[ "$vlan_ip_1" =~ "10.176." ]]; then
        vlan_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $vlan_ip_1)
        discovery_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $discovery_ip_1)

    elif [[ "$vlan_ip_1" =~ "10.177." ]] || [[ "$vlan_ip_1" =~ "10.178." ]] || [[ "$vlan_ip_1" =~ "10.179." ]]; then
        vlan_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $vlan_ip_1)
        discovery_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $discovery_ip_1)

    elif [[ "$vlan_ip_1" =~ "10.180." ]] || [[ "$vlan_ip_1" =~ "10.181." ]] || [[ "$vlan_ip_1" =~ "10.182." ]]; then
        vlan_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $vlan_ip_1)
        discovery_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $discovery_ip_1)

    elif [[ "$vlan_ip_1" =~ "10.183." ]] || [[ "$vlan_ip_1" =~ "10.184." ]] || [[ "$vlan_ip_1" =~ "10.185." ]]; then
        vlan_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $vlan_ip_1)
        discovery_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $discovery_ip_1)

    elif [[ "$vlan_ip_1" =~ "10.186." ]] || [[ "$vlan_ip_1" =~ "10.187." ]] || [[ "$vlan_ip_1" =~ "10.188." ]]; then
        vlan_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $vlan_ip_1)
        discovery_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $discovery_ip_1)

    elif [[ "$vlan_ip_1" =~ "10.189." ]] || [[ "$vlan_ip_1" =~ "10.190." ]] || [[ "$vlan_ip_1" =~ "10.191." ]]; then
        vlan_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $vlan_ip_1)
        discovery_ip_2=$(awk -F '.' '{print $1"."$2-32"."$3"."$4}' <<< $discovery_ip_1)

    elif [[ "$vlan_ip_1" =~ "192.168." ]]; then
        vlan_ip_2=$(awk -F '.' '{print "10.157."$3"."$4}' <<< $vlan_ip_1)
        discovery_ip_2=$(awk -F '.' '{print "10.157."$3"."$4}' <<< $discovery_ip_1)
    else
        echo "Unknown VLAN subnet: $vlan_ip_1";
        exit 1
    fi
}

function make_secondary_vlan_ip_up() {

    local vlan_id=$1
    local vlan_ip_1=$2

    echo -e "........";
    echo "Configure secondary VLAN IP:"

    # Get VLAN interface
    vlan_interface=$(ip -4 a | grep $vlan_id | grep 'state UP' | cut -d '@' -f2|cut -d ':' -f1)

    calculate_ips $vlan_ip_1 $discovery_ip_1

    if [[ "$dist_name" == "ubuntu" ]] && [[ "$dist_vers" =~ 18|20|22 ]]; then
        net_cfg="/etc/netplan/60-$vlan_ip_2.yaml"
    elif [[ "$dist_name" == "ubuntu" ]] || [[ "$dist_name" == "debian" ]]; then
        net_cfg="/etc/network/interfaces.d/60-$vlan_ip_2.cfg"
    elif [[ "$dist_name" == "centos" ]] || [[ "$dist_name" == "almalinux" ]]; then
        net_cfg="/etc/sysconfig/network-scripts/ifcfg-$vlan_interface.$vlan_id:1"
    elif [[ "$dist_name" == "opensuse" ]]; then
        net_cfg="/etc/sysconfig/network/ifcfg-$vlan_interface.$vlan_id"
    else
        echo "Unknown distribution."
        exit 1
    fi

    check_if_secondary_vlan_ip_is_up $vlan_ip_2
    if [[ $? -eq 1 ]]; then
        echo -e "\tNo secondary VLAN IP setuped. Let's setup one."
        make_network_config_template $vlan_interface $vlan_id $vlan_ip_2

        if [[ ! -e "$net_cfg" ]]; then
            cp $template $net_cfg

            # Restart network
            for attempt in $(seq 1 3); do
                sleep 3;
                check_if_secondary_vlan_ip_is_up $vlan_ip_2
                if [[ $? -eq 1 ]]; then
                    restart_network $vlan_interface $vlan_id
                else
                    break
                fi
            done
        else
            if [[ "$dist_name" == "opensuse" ]]; then
                cat ${template} >> ${net_cfg}
                restart_network $vlan_interface $vlan_id
            else
                diff -q $template $net_cfg >/dev/null
                if [[ $? -eq 1 ]]; then
                    echo -e "\tNetwork config file for $vlan_ip_2 already exists."
                    echo -e "\t* Network config file exists but content differs from template."
                    echo -e "\t  Ensure $vlan_ip_2 is up and running by either removing"
                    echo -e "\t  $net_cfg and rerun script"
                    echo -e "\t  or configure it manually and try to run script again."
                    return 1;
                else
                    echo -e "\tNetwork config file for $vlan_ip_2 already exists."
                    echo -e "The contents are valid. Try to restart networking."

                    # Restart network
                    restart_network $vlan_interface $vlan_id
                fi
            fi
        fi
    else
        echo -e "\tSecondary IP already exists. Skiping..."
    fi

    check_if_secondary_vlan_ip_is_up $vlan_ip_2
    [[ $? -eq 0 ]] && {  echo "Configure secondary VLAN IP. Done."; return 0; } || { return 1; }
}

function load_multipath_modules() {

    modprobe dm_multipath
	modprobe dm_round_robin
}

function ensure_services_up_and_enabled() {

    echo -e "........"
    echo "Enable services:"

    if [[ "$dist_name" == "ubuntu" ]] || [[ "$dist_name" == "debian" ]]; then

        if [[ "$dist_name" == "ubuntu" ]] && [[ "$dist_vers" != "14" ]]; then
            [[ "$systemctl" -eq 1 ]] && systemctl enable iscsid &>/dev/null
        elif [[ "$dist_name" == "debian" ]] && [[ "$dist_vers" != "8" ]]; then
            [[ "$systemctl" -eq 1 ]] && systemctl enable iscsid &>/dev/null
        elif [[ "$dist_name" == "ubuntu" ]] && [[ "$dist_vers" == "14" ]]; then
            [[ "$systemctl" -eq 1 ]] && systemctl enable open-iscsi &>/dev/null
        elif [[ "$dist_name" == "debian" ]] && [[ "$dist_vers" == "8" ]]; then
            [[ "$systemctl" -eq 1 ]] && systemctl enable open-iscsi &>/dev/null
        fi
    elif
        [[ "$dist_name" == "centos" ]] || [[ "$dist_name" == "almalinux" ]]; then
            if [[ "$systemctl" -eq 1 ]]; then
                systemctl enable multipathd &>/dev/null; systemctl enable iscsid &>/dev/null;
                systemctl start multipathd &>/dev/null
            else
                chkconfig iscsi on &>/dev/null; chkconfig multipathd on &>/dev/null;
                service multipathd start &>/dev/null
            fi

    else
        echo -e "Unknown distribution!"
    fi

    echo "Enable services. Done."
}

function install_required_packages() {

    echo -e "........"
    echo -e "Installing required packages:"
    if [[ "$dist_name" == "ubuntu" ]] || [[ "$dist_name" == "debian" ]]; then
        export DEBIAN_FRONTEND=noninteractive
        [[ ! $(which iscsiadm 2>/dev/null) ]] && { apt -qq update 1>/dev/null &&  apt -yq install open-iscsi 1>/dev/null; }
        [[ ! $(which multipath 2>/dev/null) ]] && { apt -qq update 1>/dev/null && apt -yq install multipath-tools 1>/dev/null; }
    elif [[ "$dist_name" == "centos" ]] || [[ "$dist_name" == "almalinux" ]]; then
        [[ ! $(which iscsiadm 2>/dev/null) ]] && { yum -y install -d1 iscsi-initiator-utils 1>/dev/null; }
        [[ ! $(which multipath 2>/dev/null) ]] && { yum -y install -d1 device-mapper-multipath 1>/dev/null; }
    elif [[ "$dist_name" == "opensuse" ]]; then
        [[ ! $(which iscsiadm 2>/dev/null) ]] && { zypper -q install -y open-iscsi  1>/dev/null; }
        [[ ! $(which multipath 2>/dev/null) ]] && { zypper -q install -y multipath-tools 1>/dev/null; }
    else
        echo "Unknown packaging system!"
        exit 1
    fi

    load_multipath_modules

    echo -e "Installing required packages. Done."
}

function configure_iscsi() {

    echo -e "........"
    echo -e "Configure iscsid:"
    if [[ $(grep 'node.startup = manual' /etc/iscsi/iscsid.conf) ]]; then
        echo -e "\tUpdating iscsid.conf file..."
        sed -i.bak 's/node.startup = manual/node.startup = automatic/g' /etc/iscsi/iscsid.conf
    fi
    echo -e "Configure iscsid. Done."
}

function create_multipath_config() {

    echo -e "........"
    echo -e "Create multipath config:"

	cat <<- EOF > /etc/multipath.conf
defaults {
       polling_interval       3
       fast_io_fail_tmo 5
       path_selector              "round-robin 0"
       rr_min_io                    100
       rr_weight                    priorities
       failback                    immediate
       user_friendly_names     yes
}

blacklist {
         devnode "^(ram|raw|loop|fd|md|dm-|sr|scd|st)[0-9]*"
         devnode "^hd[a-z][[0-9]*]"
         devnode "^vd[a-z]"
         devnode "^cciss!c[0-9]d[0-9]*[p[0-9]*]"
         device {
               vendor  "Micron"
               product ".*"
         }
         device {
               vendor  "Intel"
               product ".*"
         }
         device {
               vendor  "DELL"
               product ".*"
         }
}

devices {
        device {
                vendor "StorPool"
                product "iSCSI DISK"
                path_grouping_policy group_by_prio
                path_checker tur
                hardware_handler "1 alua"
        }
}
EOF
    echo -e "Create multipath config. Done."
}

function change_initiator_name() {

    local initiator_name=$1

    echo -e "........"
    echo -e "Change initiator name:"

    if [[ ! $(grep $initiator_name /etc/iscsi/initiatorname.iscsi) ]]; then
        echo -e "\tUpdate initiator name to $initiator_name"
        sed -i "s/InitiatorName=.*/InitiatorName=$initiator_name/g" /etc/iscsi/initiatorname.iscsi
    fi

    echo -e "Change initiator name. Done."
}

function clean_mpath_bindings() {

    echo -e "........"
    echo -e "Clean mpath bindings:"
    [[ -f /etc/multipath/bindings ]] && sed -i "/^mpath.*/d" /etc/multipath/bindings
    if [[ $(ls /dev/mapper/mpath* 2>/dev/null) ]]; then
        echo -e "\tmpath entried found. Cleaning..."
        for m in $(ls /dev/mapper/mpath* 2>/dev/null); do
            multipath -f $m
        done
    fi
    multipath >/dev/null
    echo -e "Clean mpath bindings. Done."
}

function configure_multipath() {

    echo -e "\t........"
    echo -e "\tConfigure multipath:"
    dev_name=$(ls -l /dev/disk/by-path/|grep "$target_name"|grep "$discovery_ip_1"|awk '{print $11}'|sed 's/\.\.\/\.\.\///g')

    if [[ $(multipath -ll|grep -Eo '.*dm'|awk '{if (NF == 3){print $2} else if(NF == 2){print $1}}'|sed 's/[()]//g'|grep StorPool) ]]; then
        wwid=$(multipath -ll|grep -Eo '.*dm'|awk '{if (NF == 3){print $2} else if(NF == 2){print $1}}'|sed 's/[()]//g'|grep StorPool)
    else
        wwid=$(udevadm info --query=property --name=/dev/$dev_name | grep -Po 'ID_SERIAL=\K(.*)')
    fi
    vol_name=$(cut -d ':' -f3 <<< $target_name)

    if [[ $(grep "^$vol_name" /etc/multipath/bindings 2>/dev/null) ]]; then
        sed -i "s/^$vol_name .*/$vol_name $wwid/" /etc/multipath/bindings
    else
        echo "$vol_name $wwid" >> /etc/multipath/bindings
    fi

    multipath $vol_name &>/dev/null
    echo -e "\tConfigure multipath. Done."
}

function attach_volume() {

    local discovery_ip_1=$1
    local discovery_ip_2=$2

    portals=($discovery_ip_1 $discovery_ip_2)
    for portal in ${portals[*]}; do

        echo -e "........"
        echo -e "Discover targets on portal $portal:"

        if [[ $(iscsiadm --mode discovery -t sendtargets --portal $portal) ]]; then
            echo -e "\tTargets were discovered on $portal"
        else
            echo -e "\tError: Can't discover targets on $portal. Try again later."
            exit 1;
        fi

        echo -e "Discover targets on portals. Done."

        target_name=$(iscsiadm -m node -o show|grep 'node.name'|awk '{print $3}'|uniq)

        echo -e "........"
        echo -e "Login on portal $portal:"
        if [[ ! $(iscsiadm -m session -o show 2>/dev/null|grep $portal) ]]; then
            if [[ $(iscsiadm -m node -T $target_name -p $portal -l) ]]; then
                echo -e "\tLogged in to $target_name on $portal"
                sleep 5
                configure_multipath

            else
                echo "Can't login to $target_name on portal $portal"
            fi
        else
            echo -e "\tSession already exists."
            configure_multipath
        fi
        echo -e "Login on portal $portal. Done."
    done
}

function detach_volume() {

    echo -e "........"
    echo -e "Detach volume:"

    calculate_ips $vlan_ip_1 $discovery_ip_1
    vol_name=$(iscsiadm -m session -o show 2>/dev/null|grep -E "$discovery_ip_1|$discovery_ip_2"|grep -Po "iqn.2019-03.com.cherryservers:cherryservers:\K(.*)"|awk '{print $1}')

    if [[ $vol_name ]]; then

        vol_name=$(echo $vol_name|awk '{print $1}')
        mnt=$(grep $vol_name /proc/mounts 2>/dev/null)
        if [[ $mnt ]]; then
            echo -e "\tVolume $vol_name is mounted. Please unmount it first and try again."
            exit 1
        fi

        target_name=$(iscsiadm -m node -o show|grep 'node.name'|awk '{print $3}'|uniq)
        for portal in $(iscsiadm -m session | grep $target_name | awk {'print $3'} | egrep -o '([[:digit:]]{1,3}\.){3}[[:digit:]]{1,3}'); do
            echo -e "\tLog out from $target_name on $portal"
            iscsiadm --mode node --targetname $target_name --portal $portal --logout &>/dev/null
            sed -i "/^$vol_name.*/d" /etc/multipath/bindings
            multipath -f $vol_name &>/dev/null
        done
        clean_mpath_bindings

        rm -rf /etc/iscsi/{nodes,send_targets}/*
        rm -rf /var/lib/iscsi/{nodes,send_targets}/*
    else
        echo -e "\tCan't find any active sessions with provided subnets"
    fi

    echo -e "Detach volume. Done."
}

function get_status() {

    local vol_name=$1

    if [[ -f /etc/multipath/bindings ]]; then
        wwid=$(grep "${vol_name:-none}" /etc/multipath/bindings|awk '{print $2}')
    fi

    echo -e "#####################"
    echo -e "Configuration report:"

    if [[ -b "/dev/mapper/$vol_name" ]]; then
        echo -e "\tBlock device /dev/mapper/$vol_name is ready. Format, mount and use it."
    elif [[ -b "/dev/mapper/$wwid" ]]; then
        echo -e "\tBlock device found as WWID: /dev/mapper/$wwid. Releading devmap..."
        multipath -r >/dev/null
        if [[ -b "/dev/mapper/$vol_name" ]]; then
            echo -e "\tBlock device /dev/mapper/$vol_name is ready. Format, mount and use it."
        fi
    else
        echo -e "\tCan't find block device /dev/mapper/$vol_name. Please contact support for assistance or try again."
    fi
    echo -e "Configuration report. Done"
    echo -e "#####################"
}

function check_if_portals_reachable() {

    local discovery_ip_1=$1
    local discovery_ip_2=$2

    echo -e "........"
    echo -e "Check portal IPs:"

    portals=($discovery_ip_1 $discovery_ip_2)

    for portal in ${portals[*]}; do
        if ! ping -q -c 3 "${portal}" >/dev/null; then
            echo -e "\tIt seems that internal VLAN is not ready yet for $portal address."
            echo -e "\tPlease try to run command again a bit later."
            echo -e "Check portal IPs. Done."
            return 1
        fi
    done

    echo -e "Check portal IPs. Done."

    return 0
}

if [[ "$attach" == "yes" ]]; then

    detect_distribution
    make_secondary_vlan_ip_up $vlan_id $vlan_ip_1; [[ $? -eq 0 ]] || { echo "Unable to setup secondary IP!"; exit 1; }
    check_if_portals_reachable $discovery_ip_1 $discovery_ip_2; [[ $? -eq 0 ]] || exit 1
    install_required_packages
    create_multipath_config
    change_initiator_name $initiator
    configure_iscsi
    reboot_iscsid
    ensure_services_up_and_enabled
    change_initiator_name $initiator
    reboot_iscsid
    attach_volume $discovery_ip_1 $discovery_ip_2
    clean_mpath_bindings
    get_status $vol_name
fi

if [[ "$detach" == "yes" ]]; then

    detach_volume $discovery_ip_1 $vlan_ip_1
fi