diff --git a/tools/11.deletcd.yml b/tools/11.deletcd.yml
index 709c670..9bdcd90 100644
--- a/tools/11.deletcd.yml
+++ b/tools/11.deletcd.yml
@@ -1,4 +1,4 @@
-# WARNNING:  this playbook will clean the etcd {{ NODE_TO_DEL }} 
+# WARNNING:  this playbook will clean the etcd {{ ETCD_TO_DEL }} 
 # USAGE:     easzctl del-etcd 1.1.1.1
 
 - hosts: localhost 
@@ -30,6 +30,7 @@
                 endpoint health; \
               done'
       register: ETCD_CLUSTER_STATUS
+      ignore_errors: true
 
     - debug: var="ETCD_CLUSTER_STATUS.stdout"
 
@@ -55,10 +56,10 @@
       delegate_to: "{{ RUNNING_NODE.stdout }}"
       when: "ETCD_ID.stdout != ''"
   
-    - name: clean etcd {{ NODE_TO_DEL }} if possible
+    - name: clean etcd {{ ETCD_TO_DEL }} if possible
       shell: "ansible-playbook {{ base_dir }}/roles/clean/clean_node.yml \
-                -e NODE_TO_CLEAN={{ NODE_TO_DEL }} \
-                -e DEL_ETCD=yes >> /tmp/ansible-playbook.log 2>&1 \
+                -e NODE_TO_CLEAN={{ ETCD_TO_DEL }} \
+                -e DEL_ETCD=yes >> /tmp/ansible-`date +'%Y%m%d%H%M%S'`.log 2>&1 \
               || echo 'data not cleaned on {{ ETCD_TO_DEL }}'"
       register: CLEAN_STATUS
 
@@ -71,5 +72,5 @@
         warn: false
 
     - name: reconfig and restart the etcd cluster
-      shell: "ansible-playbook {{ base_dir }}/02.etcd.yml > /tmp/ansible-playbook.log 2>&1"
+      shell: "ansible-playbook {{ base_dir }}/02.etcd.yml >> /tmp/ansible-`date +'%Y%m%d%H%M%S'`.log 2>&1"
     when: "groups['etcd']|length > 1 and ETCD_TO_DEL in groups['etcd']" 
diff --git a/tools/12.delnode.yml b/tools/12.delnode.yml
index da49d23..d217ec2 100644
--- a/tools/12.delnode.yml
+++ b/tools/12.delnode.yml
@@ -14,7 +14,7 @@
     shell: "ansible-playbook {{ base_dir }}/roles/clean/clean_node.yml \
               -e NODE_TO_CLEAN={{ NODE_TO_DEL }} \
               -e DEL_NODE=yes \
-              -e DEL_LB=yes >> /tmp/ansible-playbook.log 2>&1 \
+              -e DEL_LB=yes >> /tmp/ansible-`date +'%Y%m%d%H%M%S'`.log 2>&1 \
             || echo 'data not cleaned on {{ NODE_TO_DEL }}'"
     register: CLEAN_STATUS
 
@@ -23,3 +23,9 @@
   - name: run kubectl delete node {{ NODE_TO_DEL }}
     shell: "{{ bin_dir }}/kubectl delete node {{ NODE_TO_DEL }}"
     ignore_errors: true
+
+  # lineinfile is inadequate to delete lines between some specific line range
+  - name: remove the node's entry in hosts
+    shell: 'sed -i "/^\[kube-node/,/^\[harbor/ {/^{{ NODE_TO_DEL }}[^0-9]*$/d}" {{ base_dir }}/hosts'
+    args:
+      warn: false
diff --git a/tools/13.delmaster.yml b/tools/13.delmaster.yml
index 937e58f..db2996d 100644
--- a/tools/13.delmaster.yml
+++ b/tools/13.delmaster.yml
@@ -15,7 +15,7 @@
               -e NODE_TO_CLEAN={{ NODE_TO_DEL }} \
               -e DEL_MASTER=yes \
               -e DEL_NODE=yes \
-              -e DEL_LB=yes >> /tmp/ansible-playbook.log 2>&1 \
+              -e DEL_LB=yes >> /tmp/ansible-`date +'%Y%m%d%H%M%S'`.log 2>&1 \
             || echo 'data not cleaned on {{ NODE_TO_DEL }}'"
     register: CLEAN_STATUS
 
@@ -24,3 +24,9 @@
   - name: run kubectl delete node {{ NODE_TO_DEL }}
     shell: "{{ bin_dir }}/kubectl delete node {{ NODE_TO_DEL }}"
     ignore_errors: true
+
+  # lineinfile is inadequate to delete lines between some specific line range
+  - name: remove the master's entry in hosts
+    shell: 'sed -i "/^\[kube-master/,/^\[harbor/ {/^{{ NODE_TO_DEL }}[^0-9]*$/d}" {{ base_dir }}/hosts'
+    args:
+      warn: false
diff --git a/tools/easzctl b/tools/easzctl
index c90b525..fc7b6d4 100755
--- a/tools/easzctl
+++ b/tools/easzctl
@@ -158,9 +158,6 @@ function del-node() {
     # 
     ansible-playbook $BASEPATH/tools/12.delnode.yml -e NODE_TO_DEL=$1 || { echo "[ERROR] Failed to delete 'kube-node': $1!"; return 2; }
 
-    # remove node in ansible hosts
-    sed -i '/^\[kube-node/,/^\[harbor/{/^'"$1"'[^0-9]/d}' $BASEPATH/hosts
-
     # save current cluster context if needed
     [ -f "$BASEPATH/.cluster/current_cluster" ] && save_context
     return 0
@@ -173,10 +170,6 @@ function del-master() {
     # 
     ansible-playbook $BASEPATH/tools/13.delmaster.yml -e NODE_TO_DEL=$1 || { echo "[ERROR] Failed to delete 'kube-master': $1!"; return 2; }
 
-    # remove node in ansible hosts
-    sed -i '/^\[kube-master/,/^\[kube-node/{/^'"$1"'[^0-9]/d}' $BASEPATH/hosts
-    sed -i '/^\[kube-node/,/^\[harbor/{/^'"$1"'[^0-9]/d}' $BASEPATH/hosts
-
     # reconfig kubeconfig in ansible manage node
     ansible-playbook $BASEPATH/roles/deploy/deploy.yml -t create_kctl_cfg