diff --git a/postgres/user.sql b/postgres/user.sql
index 35a7896..18b58f1 100644
--- a/postgres/user.sql
+++ b/postgres/user.sql
@@ -1,39 +1,39 @@
-DROP USER IF EXISTS report;
-
-SET password_encryption = 'scram-sha-256';
-
-CREATE ROLE report WITH 
-    LOGIN
-	NOSUPERUSER
-	NOCREATEDB
-	NOCREATEROLE
-	INHERIT
-	NOREPLICATION
-	CONNECTION LIMIT -1
-	PASSWORD 'report';
-	
---------------------grant--------------------------------------------------
-    
-GRANT USAGE ON SCHEMA lgdat TO report;
-
-GRANT SELECT /*, UPDATE, INSERT, DELETE*/ ON ALL TABLES IN SCHEMA lgdat TO report;
-
-GRANT USAGE ON ALL SEQUENCES IN SCHEMA lgdat TO report;
-
-ALTER DEFAULT PRIVILEGES IN SCHEMA lgdat GRANT SELECT/*, UPDATE, INSERT, DELETE*/ ON TABLES TO report;
-
-ALTER DEFAULT PRIVILEGES IN SCHEMA lgdat GRANT USAGE ON SEQUENCES TO report;
-
----------------------------revoke---------------------------------------
-
-REVOKE USAGE ON SCHEMA lgdat FROM report;
-
-REVOKE USAGE ON SCHEMA lgdat FROM report;
-
-REVOKE SELECT , UPDATE, INSERT, DELETE ON ALL TABLES IN SCHEMA lgdat FROM report;
-
-REVOKE USAGE ON ALL SEQUENCES IN SCHEMA lgdat FROM report;
-
-ALTER DEFAULT PRIVILEGES IN SCHEMA lgdat REVOKE SELECT, UPDATE, INSERT, DELETE ON TABLES FROM report;
-
-ALTER DEFAULT PRIVILEGES IN SCHEMA lgdat REVOKE USAGE ON SEQUENCES FROM report;
+DROP USER IF EXISTS api;
+
+SET password_encryption = 'scram-sha-256';
+
+CREATE ROLE api WITH 
+    LOGIN
+	NOSUPERUSER
+	NOCREATEDB
+	NOCREATEROLE
+	INHERIT
+	NOREPLICATION
+	CONNECTION LIMIT -1
+	PASSWORD 'api';
+	
+--------------------grant--------------------------------------------------
+    
+GRANT USAGE ON SCHEMA lgdat TO api;
+
+GRANT SELECT /*, UPDATE, INSERT, DELETE*/ ON ALL TABLES IN SCHEMA lgdat TO api;
+
+GRANT USAGE ON ALL SEQUENCES IN SCHEMA lgdat TO api;
+
+ALTER DEFAULT PRIVILEGES IN SCHEMA lgdat GRANT SELECT/*, UPDATE, INSERT, DELETE*/ ON TABLES TO api;
+
+ALTER DEFAULT PRIVILEGES IN SCHEMA lgdat GRANT USAGE ON SEQUENCES TO api;
+
+---------------------------revoke---------------------------------------
+
+REVOKE USAGE ON SCHEMA lgdat FROM api;
+
+REVOKE USAGE ON SCHEMA lgdat FROM api;
+
+REVOKE SELECT , UPDATE, INSERT, DELETE ON ALL TABLES IN SCHEMA lgdat FROM api;
+
+REVOKE USAGE ON ALL SEQUENCES IN SCHEMA lgdat FROM api;
+
+ALTER DEFAULT PRIVILEGES IN SCHEMA lgdat REVOKE SELECT, UPDATE, INSERT, DELETE ON TABLES FROM api;
+
+ALTER DEFAULT PRIVILEGES IN SCHEMA lgdat REVOKE USAGE ON SEQUENCES FROM api;
diff --git a/ubuntu/net-scan.sh b/ubuntu/net-scan.sh
new file mode 100644
index 0000000..d3587c9
--- /dev/null
+++ b/ubuntu/net-scan.sh
@@ -0,0 +1,108 @@
+usage="$(basename "$0") [OPTIONS] -- program to retrieve network devices and show IP address paired with the device name
+where:
+	-h	show this help text
+	-i	set the IP interface to check (default: 1) - check available IPs list with [-l] option
+	-l	list the available IP addresses
+	-a	show all network IPs, even if no computer name is found
+	-m	show MAC address
+	-b	show devices brand when no other information is available (if nmap installed and if can be found)"
+
+myip=1
+shownoname=false
+showmac=false
+showbrand=false
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+ORANGE='\033[0;33m'
+NC='\033[0m'
+
+while getopts ':halmbi:' option; do
+	case "$option" in
+		h) echo "$usage"
+			exit 0
+	   		;;
+		a) shownoname=true
+			;;
+		l) sudo nm-tool | grep -i 'address' | grep -Po '[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+' | nl -n 'ln'
+		   	exit 0
+		   	;;
+		m) showmac=true
+			;;
+		b) showbrand=true
+			;;
+   		i) myip=$OPTARG
+			if [ -z $(sudo nm-tool | grep -i 'address' | grep -Po '[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+' | sed -n "$myip"p) ]; then
+				echo "there is no such interface, try the [-l] option"
+				exit 1
+			fi
+	   		;;
+	   	:) printf "missing argument for -%s\n" "$OPTARG" >&2
+	   		exit 1
+		   	;;
+		\?) printf "illegal option: -%s\n" "$OPTARG" >&2
+		   	exit 1
+		   	;;
+	esac
+done
+shift $((OPTIND - 1))
+
+# get if nmap is installed
+nmapInstalled=$(whereis nmap)
+if [ -z "$nmapInstalled" ]; then
+	showbrand=false
+fi
+
+maxwait=0.1;
+# get starter IP address
+IFS=. read -r i1 i2 i3 i4 <<< $(sudo nm-tool | grep -i 'address' | grep -Po '[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+' | sed -n "$myip"p)
+IFS=. read -r m1 m2 m3 m4 <<< $(sudo nm-tool | grep -i 'prefix' | grep -Po '[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+' | sed -n "$myip"p)
+si1=$(($i1 & $m1))
+si2=$(($i2 & $m2))
+si3=$(($i3 & $m3))
+si4=$(($i4 & $m4))
+# get my HW address
+myhwaddr=$(ifconfig | grep -B 1 "$i1.$i2.$i3.$i4" | grep -oP '([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})' | sed -n "$myip"p)
+# get number of IPs in network
+iprange=$(sudo nm-tool | grep -i 'prefix' | grep -Po '\s[0-9]+' | grep -Po '[0-9]+' | sed -n "$myip"p)
+iprange=$(( 2**(32-$iprange) -1 ))
+#  cycle through IPs
+for((i=1;i<$iprange;i++)); do
+	# calulate IP
+	ci4=$(($si4 + $i))
+	ci3=$(($si3 + ($ci4 / 256) )); ci4=$(($ci4 % 256))
+	ci2=$(($si2 + ($ci3 / 256) )); ci3=$(($ci3 % 256))
+	ci1=$(($si1 + ($ci2 / 256) )); ci2=$(($ci2 % 256))
+	# get computer name
+	result=$(timeout $maxwait nmblookup -A "$ci1.$ci2.$ci3.$ci4" | sed -n 2p | grep -Po '\t.+?\s' | xargs)
+	hwaddress=$(arp "$ci1.$ci2.$ci3.$ci4" | grep -Po '([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})')
+	if [ -z "$result" ] && [ ! -z "$hwaddress" ] && [ $shownoname == true ]; then
+		result="???"
+	fi
+	# print if response given
+	if [ ! -z "$result" ]; then
+		toprint="$ci1.$ci2.$ci3.$ci4"
+		if [ $showmac == true ]; then
+			if [ -z "$hwaddress" ]; then
+				hwaddress=$myhwaddr
+			fi
+			toprint="$toprint ( $hwaddress )"
+		fi
+		myhost=$(grep "$ci1.$ci2.$ci3.$ci4" /etc/hosts | grep -oP '\s.+' | xargs)
+		if [ ! -z "$myhost" ]; then
+			result="$result ( ${GREEN}$myhost${NC} )"
+		fi
+		if [ "$ci1.$ci2.$ci3.$ci4" == "$i1.$i2.$i3.$i4" ]; then
+			result="$result ( ${RED}THIS DEVICE${NC} )"
+		fi
+		# if nothing found and nmap installed get device brand
+		if [ "$result" == "???" ] && [ $showbrand == true ]; then
+			result=$(sudo nmap -sP "$ci1.$ci2.$ci3.$ci4" | grep 'MAC Address' | grep -Po '\(.+?\)')
+			if [ "$result" == "(Unknown)" ]; then
+				result="???"
+			else
+				result="??? ${ORANGE}$result${NC}"
+			fi
+		fi
+		echo -e "$toprint\t=>\t$result"
+	fi
+done
\ No newline at end of file
diff --git a/ubuntu/network.md b/ubuntu/network.md
new file mode 100644
index 0000000..e69de29
diff --git a/ubuntu/scan.sh b/ubuntu/scan.sh
new file mode 100644
index 0000000..f727794
--- /dev/null
+++ b/ubuntu/scan.sh
@@ -0,0 +1,12 @@
+#!/bin/bash
+
+is_alive_ping()
+{
+  ping -c 1 $1 > /dev/null
+  [ $? -eq 0 ] && echo Node with IP: $i is up.
+}
+
+for i in 192.168.1.{1..255} 
+do
+is_alive_ping $i & disown
+done
\ No newline at end of file
diff --git a/ubuntu/systemd.md b/ubuntu/systemd.md
new file mode 100644
index 0000000..19a12fc
--- /dev/null
+++ b/ubuntu/systemd.md
@@ -0,0 +1,24 @@
+save in //etc/systemd/system/this_file.service
+
+```
+[Unit]
+Description=Redis persistent key-value database
+After=network.target
+
+[Service]
+ExecStart=/usr/bin/node //var/wwww/forecast_api/index.js
+User=fc
+Restart=always
+StandardOutput=syslog
+StandardError=syslog
+WorkingDirectory=//var/www/forecast_api
+
+[Install]
+WantedBy=multi-user.target
+```
+
+`sudo systemctl daemon-reload`
+
+`sudo systemctl enable forecast_api`
+
+https://www.axllent.org/docs/view/nodejs-service-with-systemd/
\ No newline at end of file
diff --git a/ubuntu/users.md b/ubuntu/users.md
index 9e2c2c6..a9ac694 100644
--- a/ubuntu/users.md
+++ b/ubuntu/users.md
@@ -1,8 +1,20 @@
-`adduser` -> high-level
-`useradd` -> low-level
-
-adduser fc_api 
-usermod -a -G sudo fc_api
-
-chown user_name directory/
-chgrp user_name directory/
\ No newline at end of file
+add a new user  and then add to multiple groups
+`adduser user_name`
+`usermod -a -G adm,sudo user_name`
+`chfn` -> changes full name
+
+change a ownership
+`chown file_or_dir user_name`
+`chgrp file_or_dir user_name`
+
+
+delete user
+`userdel user_name`
+`adduser` -> high-level
+`useradd` -> low-level
+
+adduser fc_api 
+usermod -a -G sudo fc_api
+
+chown user_name directory/
+chgrp user_name directory/