集群运维自动化工具ansible的安装与使用(包括模块与playbook使用)第2/2页,ansibleplaybook



10、优化ansible-playbook运行时间
默认playbook是进行客户端fact搜集,一般如果你配置里没有使用fact的话,可以关闭这样就能减少运行时间
没有优化的时候

[root@puppet ansible]# cat shell.yml 
---
- hosts: vpn
 remote_user: test
# gather_facts: False
 tasks:
 - name: echo hi
  shell: echo "hi"
[root@puppet ansible]# time ansible-playbook shell.yml -u test --private-key=/root/denglei -k
 [WARNING]: The version of gmp you have installed has a known issue regarding
timing vulnerabilities when used with pycrypto. If possible, you should update
it (ie. yum update gmp).
 
SSH password: 
 
PLAY [vpn] ******************************************************************** 
 
GATHERING FACTS *************************************************************** 
ok: [172.17.0.10]
 
TASK: [echo hi] *************************************************************** 
changed: [172.17.0.10]
 
PLAY RECAP ******************************************************************** 
172.17.0.10       : ok=2  changed=1  unreachable=0  failed=0  
 
real  0m8.396s
user  0m0.796s
sys 0m0.158s
[root@puppet ansible]# time ansible-playbook shell.yml -u test --private-key=/root/denglei -k
 [WARNING]: The version of gmp you have installed has a known issue regarding
timing vulnerabilities when used with pycrypto. If possible, you should update
it (ie. yum update gmp).
 
SSH password: 
 
PLAY [vpn] ******************************************************************** 
 
GATHERING FACTS *************************************************************** 
ok: [172.17.0.10]
 
TASK: [echo hi] *************************************************************** 
changed: [172.17.0.10]
 
PLAY RECAP ******************************************************************** 
172.17.0.10       : ok=2  changed=1  unreachable=0  failed=0  
 
real  0m3.309s
user  0m0.724s
sys 0m0.108s
[root@puppet ansible]# time ansible-playbook shell.yml -u test --private-key=/root/denglei -k
 [WARNING]: The version of gmp you have installed has a known issue regarding
timing vulnerabilities when used with pycrypto. If possible, you should update
it (ie. yum update gmp).
 
SSH password: 
 
PLAY [vpn] ******************************************************************** 
 
GATHERING FACTS *************************************************************** 
ok: [172.17.0.10]
 
TASK: [echo hi] *************************************************************** 
changed: [172.17.0.10]
 
PLAY RECAP ******************************************************************** 
172.17.0.10       : ok=2  changed=1  unreachable=0  failed=0  
 
 
real  0m3.409s
user  0m0.716s
sys 0m0.099s

可以看到第一次8s,后2次都是3s
下面是优化后(未使用fact)

[root@puppet ansible]# cat shell.yml 
---
- hosts: vpn
 remote_user: test
 gather_facts: False
 tasks:
 - name: echo hi
  shell: echo "hi"
[root@puppet ansible]# time ansible-playbook shell.yml -u test --private-key=/root/denglei -k
 [WARNING]: The version of gmp you have installed has a known issue regarding
timing vulnerabilities when used with pycrypto. If possible, you should update
it (ie. yum update gmp).
 
SSH password: 
 
PLAY [vpn] ******************************************************************** 
 
TASK: [echo hi] *************************************************************** 
changed: [172.17.0.10]
 
PLAY RECAP ******************************************************************** 
172.17.0.10       : ok=1  changed=1  unreachable=0  failed=0  
 
 
real  0m2.758s
user  0m0.585s
sys 0m0.096s
[root@puppet ansible]# time ansible-playbook shell.yml -u test --private-key=/root/denglei -k
 [WARNING]: The version of gmp you have installed has a known issue regarding
timing vulnerabilities when used with pycrypto. If possible, you should update
it (ie. yum update gmp).
 
SSH password: 
 
PLAY [vpn] ******************************************************************** 
 
TASK: [echo hi] *************************************************************** 
changed: [172.17.0.10]
 
PLAY RECAP ******************************************************************** 
172.17.0.10       : ok=1  changed=1  unreachable=0  failed=0  
 
real  0m2.359s
user  0m0.565s
sys 0m0.077s

运行时间就是2s
11、自定义模块
默认的模块放到/usr/share/ansible
在这个目录创建一个目录hostname,然后把下面文件放到此目录

15:03:26 # cat /usr/share/ansible/hostname/hostname 
#!/bin/bash
#This script is modify system hostname
set -e
# This is potentially dangerous
source ${1}
OLDHOSTNAME="$(hostname)"
CHANGED="False"
if [ ! -z "$hostname" -a "${hostname}x" != "${OLDHOSTNAME}x" ];
then
hostname $hostname
OLDHOSTNAME="$hostname"
CHANGED="True"
fi
echo "hostname=${OLDHOSTNAME} changed=${CHANGED}"
exit 0

查看一下vpn的当前hostname

15:03:29 # ansible vpn -m shell -a "hostname" -u test --private-key=denglei -k
SSH password: 
172.17.0.10 | success | rc=0 >>
ip-10-10-32-34

然后编写playbook

15:04:14 # cat /etc/ansible/hostname.yml 
- name: Test the hostname file
 hosts: vpn
 tasks:
  - name: Set the hostname
   hostname: hostname=ip-10-10-32-34

 运行这个模块

15:04:37 # ansible-playbook hostname.yml -u test --private-key=denglei -M /usr/share/ansible/hostname -k
SSH password: 
 
PLAY [Test the hostname file] ************************************************* 
 
GATHERING FACTS *************************************************************** 
ok: [172.17.0.10]
 
TASK: [Set the hostname] ****************************************************** 
ok: [172.17.0.10]
 
PLAY RECAP ******************************************************************** 
172.17.0.10       : ok=2  changed=0  unreachable=0  failed=0

然后修改一下hostname.yml的主机名

16:20:00 # cat hostname.yml 
- name: Test the hostname file
 hosts: vpn
 tasks:
  - name: Set the hostname
   hostname: hostname=ip-10-10-32-34-test

 在playbook运行

16:26:46 # ansible-playbook hostname.yml -u test --private-key=denglei -M /usr/share/ansible/hostname -k -K -s
SSH password: 
sudo password [defaults to SSH password]: 
 
PLAY [Test the hostname file] ************************************************* 
 
GATHERING FACTS *************************************************************** 
ok: [172.17.0.10]
 
TASK: [Set the hostname] ****************************************************** 
changed: [172.17.0.10]
 
PLAY RECAP ******************************************************************** 
172.17.0.10       : ok=2  changed=1  unreachable=0  failed=0  
 
root@ip-10-10-10-10:/etc/ansible
16:26:55 # ansible vpn -m shell -a "hostname" -u test --private-key=denglei -k
SSH password: 
172.17.0.10 | success | rc=0 >>
ip-10-10-32-34-test

12、playbook扩展var
扩展var就是在playbook的yml里写入变量,在执行的时候制定变量从而执行,大大的提供了重复使用率
下面做个测试

[root@puppet ansible]# ansible vpn -m shell -a "ls -l /tmp/" -u test --private-key=/root/denglei -k
SSH password: 
172.17.0.10 | success | rc=0 >>
total 96
-rw-r--r-- 1 root  root  41692 May 21 13:02 config
-rw-r--r-- 1 root  root  1228 Jun 12 18:24 install_pptpd_vpn.sh
-rwxr-xr-x 1 root  root    7 Jun 13 19:33 server
-rw-rw-r-- 1 test  test    7 Jun 14 17:07 server-test
-rw-rw-r-- 1 test  test    7 Jun 18 01:44 test-server-1
-rw-rw-r-- 1 test  test    7 Jun 18 00:50 test-server-2
-rw-rw-r-- 1 test  test    7 Jun 18 00:50 test-server-3
-rw-r--r-- 1 root  root   82 Jun 12 18:21 test.log
-rw-r--r-- 1 root  root   290 Jun 12 18:21 test.sh
-rw-r--r-- 1 root  root  2444 Apr 28 2012 vpn_centos6.sh
-rw------- 1 root  root   727 Jun 10 18:21 yum_save_tx-2014-06-10-18-21UrqDAp.yumtx
-rw-rw-r-- 1 zabbix zabbix 4664 Jun 14 00:30 zabbix_agentd.log
-rw-rw-r-- 1 zabbix zabbix   5 Jun 14 00:30 zabbix_agentd.pid

可以看到有test-server-1文件
在看看playbook文件内容

[root@puppet ansible]# cat delete_vars.yml 
---
- hosts: {{host}}
 remote_user: {{user}}
 gather_facts: {{gather}}
 tasks:
 - name: if system is centos,then rm /tmp/test-server-1
  shell: rm -rf /tmp/test-server-1
  when: ansible_os_family == "RedHat"

执行前先检测一下语法是否有问题,使用--synctax-check

[root@puppet ansible]#  ansible-playbook delete_vars.yml --private-key=/root/denglei --extra-vars "host=vpn user=test gather=False" -k --syntax-check 
 [WARNING]: The version of gmp you have installed has a known issue regarding
timing vulnerabilities when used with pycrypto. If possible, you should update
it (ie. yum update gmp).
 
ERROR: Syntax Error while loading YAML script, delete_vars.yml
Note: The error may actually appear before this position: line 2, column 11
 
---
- hosts: {{host}}
     ^
This one looks easy to fix. YAML thought it was looking for the start of a 
hash/dictionary and was confused to see a second "{". Most likely this was
meant to be an ansible template evaluation instead, so we have to give the 
parser a small hint that we wanted a string instead. The solution here is to 
just quote the entire value.
 
For instance, if the original line was:
 
  app_path: {{ base_path }}/foo
 
It should be written as:
 
  app_path: "{{ base_path }}/foo"
 
We could be wrong, but this one looks like it might be an issue with
missing quotes. Always quote template expression brackets when they 
start a value. For instance:      
 
  with_items:
   - {{ foo }}
 
Should be written as:
 
  with_items:
   - "{{ foo }}"   
 
This one looks easy to fix. YAML thought it was looking for the start of a 
hash/dictionary and was confused to see a second "{". Most likely this was
meant to be an ansible template evaluation instead, so we have to give the 
parser a small hint that we wanted a string instead. The solution here is to 
just quote the entire value.
 
For instance, if the original line was:
 
  app_path: {{ base_path }}/foo
 
It should be written as:
 
  app_path: "{{ base_path }}/foo"

 可以看到有问题
 解决方法是把var的变量前后添加""或者''

[root@puppet ansible]# cat delete_vars.yml 
---
- hosts: "{{host}}"
 remote_user: "{{user}}"
 gather_facts: "{{gather}}"
 tasks:
 - name: if system is centos,then rm /tmp/test-server-1
  shell: rm -rf /tmp/test-server-1
  when: ansible_os_family == "RedHat"

然后再检测一下

[root@puppet ansible]#  ansible-playbook delete_vars.yml --private-key=/root/denglei --extra-vars "host=vpn user=test gather=False" -k --syntax-check 
 [WARNING]: The version of gmp you have installed has a known issue regarding
timing vulnerabilities when used with pycrypto. If possible, you should update
it (ie. yum update gmp).
 
playbook: delete_vars.yml

没有问题了,在运行一下

[root@puppet ansible]#  ansible-playbook delete_vars.yml --private-key=/root/denglei --extra-vars "host=vpn user=test gather=False" -k 
 [WARNING]: The version of gmp you have installed has a known issue regarding
timing vulnerabilities when used with pycrypto. If possible, you should update
it (ie. yum update gmp).
 
SSH password: 
 
PLAY [vpn] ******************************************************************** 
 
TASK: [if system is centos,then rm /tmp/test-server-1] ************************ 
fatal: [172.17.0.10] => error while evaluating conditional: ansible_os_family == "RedHat"
 
FATAL: all hosts have already failed -- aborting
 
PLAY RECAP ******************************************************************** 
      to retry, use: --limit @/root/delete_vars.retry
 
172.17.0.10       : ok=0  changed=0  unreachable=1  failed=0

无法运行,原因是我yml里制定了获取fact信息后,判断如果是redhat系列系统才删除,而我在运行的指定不收集fact,下面在指定收集fact

[root@puppet ansible]#  ansible-playbook delete_vars.yml --private-key=/root/denglei --extra-vars "host=vpn user=test gather=True" -k 
 [WARNING]: The version of gmp you have installed has a known issue regarding
timing vulnerabilities when used with pycrypto. If possible, you should update
it (ie. yum update gmp).
 
SSH password: 
 
PLAY [vpn] ******************************************************************** 
 
GATHERING FACTS *************************************************************** 
ok: [172.17.0.10]
 
TASK: [if system is centos,then rm /tmp/test-server-1] ************************ 
changed: [172.17.0.10]
 
PLAY RECAP ******************************************************************** 
172.17.0.10       : ok=2  changed=1  unreachable=0  failed=0

可以看到运行成功了

[root@puppet ansible]# ansible vpn -m shell -a "ls -l /tmp/" -u test --private-key=/root/denglei -k
SSH password: 
172.17.0.10 | success | rc=0 >>
total 92
-rw-r--r-- 1 root  root  41692 May 21 13:02 config
-rw-r--r-- 1 root  root  1228 Jun 12 18:24 install_pptpd_vpn.sh
-rwxr-xr-x 1 root  root    7 Jun 13 19:33 server
-rw-rw-r-- 1 test  test    7 Jun 14 17:07 server-test
-rw-rw-r-- 1 test  test    7 Jun 18 00:50 test-server-2
-rw-rw-r-- 1 test  test    7 Jun 18 00:50 test-server-3
-rw-r--r-- 1 root  root   82 Jun 12 18:21 test.log
-rw-r--r-- 1 root  root   290 Jun 12 18:21 test.sh
-rw-r--r-- 1 root  root  2444 Apr 28 2012 vpn_centos6.sh
-rw------- 1 root  root   727 Jun 10 18:21 yum_save_tx-2014-06-10-18-21UrqDAp.yumtx
-rw-rw-r-- 1 zabbix zabbix 4664 Jun 14 00:30 zabbix_agentd.log
-rw-rw-r-- 1 zabbix zabbix   5 Jun 14 00:30 zabbix_agentd.pid

文件删除了

13、tags
使用tag可以让playbook选择性的运行程序
查看一下客户端情况

[root@puppet ansible]# ansible vpn -m shell -a "ls -l /tmp/" -u test --private-key=/root/denglei -k
SSH password: 
172.17.0.10 | success | rc=0 >>
total 92
-rw-r--r-- 1 root  root  41692 May 21 13:02 config
-rw-r--r-- 1 root  root  1228 Jun 12 18:24 install_pptpd_vpn.sh
-rwxr-xr-x 1 root  root    7 Jun 13 19:33 server
-rw-rw-r-- 1 test  test    7 Jun 14 17:07 server-test
-rw-rw-r-- 1 test  test    7 Jun 18 00:50 test-server-2
-rw-rw-r-- 1 test  test    7 Jun 18 00:50 test-server-3
-rw-r--r-- 1 root  root   82 Jun 12 18:21 test.log
-rw-r--r-- 1 root  root   290 Jun 12 18:21 test.sh
-rw-r--r-- 1 root  root  2444 Apr 28 2012 vpn_centos6.sh
-rw------- 1 root  root   727 Jun 10 18:21 yum_save_tx-2014-06-10-18-21UrqDAp.yumtx
-rw-rw-r-- 1 zabbix zabbix 4664 Jun 14 00:30 zabbix_agentd.log
-rw-rw-r-- 1 zabbix zabbix   5 Jun 14 00:30 zabbix_agentd.pid

带有tag的yml文件

[root@puppet ansible]# cat delete_vars_tags.yml 
---
- hosts: "{{host}}"
 remote_user: "{{user}}"
 gather_facts: "{{gather}}"
 tasks:
 - name: if system is centos,then rm /tmp/test-server-1
  shell: rm -rf /tmp/test-server-1
  when: ansible_os_family == "RedHat"
  tags: server-1
 - name: if system is centos,then rm /tmp/test-server-2
  shell: rm -rf /tmp/test-server-2
  when: ansible_os_family == "RedHat"
  tags: server-2

 做一下错误检测

[root@puppet ansible]#  ansible-playbook delete_vars_tags.yml --private-key=/root/denglei --extra-vars "host=vpn user=test gather=True" --tags server-2 -k --syntax-check 
 [WARNING]: The version of gmp you have installed has a known issue regarding
timing vulnerabilities when used with pycrypto. If possible, you should update
it (ie. yum update gmp).
 
playbook: delete_vars_tags.yml

没问题在运行

[root@puppet ansible]#  ansible-playbook delete_vars_tags.yml --private-key=/root/denglei --extra-vars "host=vpn user=test gather=True" --tags server-2 -k 
 [WARNING]: The version of gmp you have installed has a known issue regarding
timing vulnerabilities when used with pycrypto. If possible, you should update
it (ie. yum update gmp).
 
SSH password: 
 
PLAY [vpn] ******************************************************************** 
 
GATHERING FACTS *************************************************************** 
ok: [172.17.0.10]
 
TASK: [if system is centos,then rm /tmp/test-server-2] ************************ 
changed: [172.17.0.10]
 
PLAY RECAP ******************************************************************** 
172.17.0.10       : ok=2  changed=1  unreachable=0  failed=0

查看一下客户端的文件情况

[root@puppet ansible]# ansible vpn -m shell -a "ls -l /tmp/" -u test --private-key=/root/denglei -k
SSH password: 
172.17.0.10 | success | rc=0 >>
total 88
-rw-r--r-- 1 root  root  41692 May 21 13:02 config
-rw-r--r-- 1 root  root  1228 Jun 12 18:24 install_pptpd_vpn.sh
-rwxr-xr-x 1 root  root    7 Jun 13 19:33 server
-rw-rw-r-- 1 test  test    7 Jun 14 17:07 server-test
-rw-rw-r-- 1 test  test    7 Jun 18 00:50 test-server-3
-rw-r--r-- 1 root  root   82 Jun 12 18:21 test.log
-rw-r--r-- 1 root  root   290 Jun 12 18:21 test.sh
-rw-r--r-- 1 root  root  2444 Apr 28 2012 vpn_centos6.sh
-rw------- 1 root  root   727 Jun 10 18:21 yum_save_tx-2014-06-10-18-21UrqDAp.yumtx
-rw-rw-r-- 1 zabbix zabbix 4664 Jun 14 00:30 zabbix_agentd.log
-rw-rw-r-- 1 zabbix zabbix   5 Jun 14 00:30 zabbix_agentd.pid

从上面测试可以看到,如果playbook使用了tag,并且在运行中指定tag,那么运行的时候仅允许此tag的信息
下面是测试运行时候不带tag的情况
先创建文件

[root@puppet ansible]# cat copy.yml 
---
- hosts: vpn
 remote_user: test
 tasks:
 - name: copy local server to client /tmp/server-test
  template: src=/tmp/server dest=/tmp/test-{{item}}
  with_items:
   - server-1
   - server-2
   - server-3
[root@puppet ansible]#  ansible-playbook copy.yml --private-key=/root/denglei -k 
 [WARNING]: The version of gmp you have installed has a known issue regarding
timing vulnerabilities when used with pycrypto. If possible, you should update
it (ie. yum update gmp).
 
SSH password: 
 
PLAY [vpn] ******************************************************************** 
 
GATHERING FACTS *************************************************************** 
ok: [172.17.0.10]
 
TASK: [copy local server to client /tmp/server-test] ************************** 
changed: [172.17.0.10] => (item=server-1)
changed: [172.17.0.10] => (item=server-2)
ok: [172.17.0.10] => (item=server-3)
 
PLAY RECAP ******************************************************************** 
172.17.0.10       : ok=2  changed=1  unreachable=0  failed=0  
 
[root@puppet ansible]# ansible vpn -m shell -a "ls -l /tmp/" -u test --private-key=/root/denglei -k
SSH password: 
172.17.0.10 | success | rc=0 >>
total 96
-rw-r--r-- 1 root  root  41692 May 21 13:02 config
-rw-r--r-- 1 root  root  1228 Jun 12 18:24 install_pptpd_vpn.sh
-rwxr-xr-x 1 root  root    7 Jun 13 19:33 server
-rw-rw-r-- 1 test  test    7 Jun 14 17:07 server-test
-rw-rw-r-- 1 test  test    7 Jun 19 19:02 test-server-1
-rw-rw-r-- 1 test  test    7 Jun 19 19:02 test-server-2
-rw-rw-r-- 1 test  test    7 Jun 18 00:50 test-server-3
-rw-r--r-- 1 root  root   82 Jun 12 18:21 test.log
-rw-r--r-- 1 root  root   290 Jun 12 18:21 test.sh
-rw-r--r-- 1 root  root  2444 Apr 28 2012 vpn_centos6.sh
-rw------- 1 root  root   727 Jun 10 18:21 yum_save_tx-2014-06-10-18-21UrqDAp.yumtx
-rw-rw-r-- 1 zabbix zabbix 4664 Jun 14 00:30 zabbix_agentd.log
-rw-rw-r-- 1 zabbix zabbix   5 Jun 14 00:30 zabbix_agentd.pid

然后再不指定tag运行

[root@puppet ansible]#  ansible-playbook delete_vars_tags.yml --private-key=/root/denglei --extra-vars "host=vpn user=test gather=True" -k
 [WARNING]: The version of gmp you have installed has a known issue regarding
timing vulnerabilities when used with pycrypto. If possible, you should update
it (ie. yum update gmp).
 
SSH password: 
 
PLAY [vpn] ******************************************************************** 
 
GATHERING FACTS *************************************************************** 
ok: [172.17.0.10]
 
TASK: [if system is centos,then rm /tmp/test-server-1] ************************ 
changed: [172.17.0.10]
 
TASK: [if system is centos,then rm /tmp/test-server-2] ************************ 
changed: [172.17.0.10]
 
PLAY RECAP ******************************************************************** 
172.17.0.10       : ok=3  changed=2  unreachable=0  failed=0  
 
[root@puppet ansible]# ansible vpn -m shell -a "ls -l /tmp/" -u test --private-key=/root/denglei -k
SSH password: 
172.17.0.10 | success | rc=0 >>
total 88
-rw-r--r-- 1 root  root  41692 May 21 13:02 config
-rw-r--r-- 1 root  root  1228 Jun 12 18:24 install_pptpd_vpn.sh
-rwxr-xr-x 1 root  root    7 Jun 13 19:33 server
-rw-rw-r-- 1 test  test    7 Jun 14 17:07 server-test
-rw-rw-r-- 1 test  test    7 Jun 18 00:50 test-server-3
-rw-r--r-- 1 root  root   82 Jun 12 18:21 test.log
-rw-r--r-- 1 root  root   290 Jun 12 18:21 test.sh
-rw-r--r-- 1 root  root  2444 Apr 28 2012 vpn_centos6.sh
-rw------- 1 root  root   727 Jun 10 18:21 yum_save_tx-2014-06-10-18-21UrqDAp.yumtx
-rw-rw-r-- 1 zabbix zabbix 4664 Jun 14 00:30 zabbix_agentd.log
-rw-rw-r-- 1 zabbix zabbix   5 Jun 14 00:30 zabbix_agentd.pid

可以看到如果不知道tag,那么运行的时候,会全部运行。
FAQ:
1、出现Error: ansible requires a json module, none found!

SSH password: 
172.17.0.4 | FAILED >> {
  "failed": true, 
  "msg": "Error: ansible requires a json module, none found!", 
  "parsed": false
}

原因是python版本过低,要不升级python要不就安装python-simplejson,下面是官方的话

On the managed nodes, you only need Python 2.4 or later, but if you are running less than Python 2.5 on the remotes, you will also need:

安装完成后,在查看

SSH password: 
172.17.0.4 | success >> {
  "changed": false, 
  "ping": "pong"
}

2、默认ansible是使用key验证的,如果使用密码登陆的服务器,使用ansible的话,要不修改ansible.cfg配置文件的ask_pass      = True给取消注释,要不就在运行命令时候加上-k,这个意思是-k, --ask-pass        ask for SSH password
3、如果客户端不在know_hosts里将会报错

paramiko: The authenticity of host '172.17.0.5' can't be established. 
The ssh-rsa key fingerprint is 397c139fd4b0d763fcffaee346a4bf6b. 
Are you sure you want to continue connecting (yes/no)?

如果想解决此问题,需要修改ansible.cfg的#host_key_checking = False取消注释
4、如果出现

[root@puppet ansible]# ansible zabbix -m shell -a "echo $TERM" -u denglei --private-key=/root/denglei
172.17.0.2 | FAILED => FAILED: not a valid DSA private key file
172.17.0.4 | FAILED => FAILED: not a valid DSA private key file

需要你在最后添加参数-k

[root@puppet ansible]# ansible zabbix -m shell -a "echo $TERM" -u denglei --private-key=/root/denglei -k
SSH password: 
172.17.0.2 | success | rc=0 >>
xterm
 
172.17.0.4 | success | rc=0 >>
xterm

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