diff --git a/tools/duckdns/.gitignore b/tools/duckdns/.gitignore
index 4c49bd7..2334d82 100644
--- a/tools/duckdns/.gitignore
+++ b/tools/duckdns/.gitignore
@@ -1 +1,2 @@
 .env
+*.log
diff --git a/tools/duckdns/install.sh b/tools/duckdns/install.sh
index 52e8008..3b1a9d1 100755
--- a/tools/duckdns/install.sh
+++ b/tools/duckdns/install.sh
@@ -1,22 +1,9 @@
 #!/bin/bash
+thisdir="$( dirname "$(readlink -e -- "${BASH_SOURCE[0]}")")"
 
 # https://www.duckdns.org/install.jsp
 
-thisdir="$( dirname "$(readlink -e -- "${BASH_SOURCE[0]}")")"
-
+croncmd="$thisdir/update.sh"
+cronjob="*/30 * * * * $croncmd" # every 30 min
+( crontab -l | grep -v -F "$croncmd" ; echo "$cronjob" ) | crontab -
 cp -f "$thisdir/.env.example" "$thisdir/.env"
-
-cat <<EOF | sudo tee /etc/cron.d/duckdns && crontab -u "$(whoami)" /etc/cron.d/duckdns
-# ------------- Minute (0 - 59)
-# | ----------- Hour (0 - 23)
-# | | --------- Day of month (1 - 31)
-# | | | ------- Month (1 - 12)
-# | | | | ----- Day of week (0 - 7) (Sunday=0 or 7)
-# | | | | |
-# * * * * * "command to be executed"
-
-# AAA обновление duckdns ip
-0 * * * * $thisdir/update.sh
-
-EOF
-
diff --git a/tools/duckdns/uninstall.sh b/tools/duckdns/uninstall.sh
index 7eee2ce..33decd6 100755
--- a/tools/duckdns/uninstall.sh
+++ b/tools/duckdns/uninstall.sh
@@ -1,3 +1,3 @@
 #!/bin/bash
 
-sudo rm -f /etc/cron.d/duckdns
+( crontab -l | grep -v -F "duckdns" ) | crontab -
diff --git a/tools/duckdns/update.sh b/tools/duckdns/update.sh
index 8c0ae18..e47d5ab 100755
--- a/tools/duckdns/update.sh
+++ b/tools/duckdns/update.sh
@@ -1,23 +1,30 @@
 #!/bin/bash
 # shellcheck disable=SC1091
-
 thisdir="$( dirname "$(readlink -e -- "${BASH_SOURCE[0]}")")"
 
+log() {
+    timestamp="$(date +'%Y-%m-%d %H:%M:%S')"
+    datestamp="$(date +'%Y-%m-%d')"
+    [ ! -d "$thisdir/log" ] && mkdir "$thisdir/log"
+    echo "[$timestamp] $*" >> "$thisdir/log/$datestamp.log"
+}
+
 [ ! -f "$thisdir/.env" ] && {
-    echo "ERROR: .env not exists"
+    log "ERROR: .env not exists"
     exit 1
 }
 
 source "$thisdir/.env"
 
 [ -z "$DUCK_TOKEN" ] && {
-    echo "ERROR: env var DUCK_TOKEN not specified"
+    log "ERROR: env var DUCK_TOKEN not specified"
     exit 1
 }
 
 [ -z "$DUCK_DOMAINS" ] && {
-    echo "ERROR: env var DUCK_DOMAINS not specified"
+    log "ERROR: env var DUCK_DOMAINS not specified"
     exit 1
 }
 
-curl -k "https://www.duckdns.org/update?domains=${DUCK_DOMAINS}&token=${DUCK_TOKEN}&ip=${DUCK_IP}"
+result=$(curl -s "https://www.duckdns.org/update?domains=${DUCK_DOMAINS}&token=${DUCK_TOKEN}&ip=${DUCK_IP}")
+log "$result"