issue for enabling/disabling ping with sysctl

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1

Hello all,

I want to use sysctl module to enable / disable ping.
When I wrote a action as "sysctl: name=net.ipv4.icmp_echo_ignore_all value=0 reload=yes state=present", indeed it cannot enable ping. I don’t know why?
The command is wrong?

Best regards,
Guo Yan

2

When you said you cannot enable ping, what behavior did you witness?

Also what version of Ansible are you using and what platform are you running the command on?

Thanks!

3

  1. Make the remote host ping disable: [root@devhost ~]# sysctl -w net.ipv4.icmp_echo_ignore_all=1

  2. Run playbook task action: sysctl: name=net.ipv4.icmp_echo_ignore_all value=0 reload=yes state=present

  3. Try to ping the remote host: It is still failed. ( I expect the remote host ping enable)

[test@test test]$ ping 192.168.126.155PING 192.168.126.155 (192.168.126.155) 56(84) bytes of data.
^C
— 192.168.126.155 ping statistics —
5 packets transmitted, 0 received, 100% packet loss, time 4430ms

My ansible version is:

[test@test test]$ ansible --version
ansible 1.5 (devel 27199dc219) last updated 2013/12/03 21:01:10 (GMT -500)

4

did you check on the host the state of the sysctl parameter before and after the ansible run?

5

Firewalls and various other factors aside, please verify 2 things:

  1. the line exists in sysctl.conf after running the module
  2. the property is set when you run “sysctl net.ipv4.icmp_echo_ignore_all”

If those two items are true, the module is working as expected.

6

It is very strange. I do two cases:

Case 1:

  1. Use command “sysctl -w net.ipv4.icmp_echo_ignore_all=1” to disable ping
  2. Use playbook sysctl module to enable ping, enabling ping would be failed.

Command sysctl -w net.ipv4.icmp_echo_ignore_all=1 doesn’t change /etc/sysctl.conf file. In this case, sysctl module also doesn’t change /etc/sysctl.conf.

Case 2:

  1. Update /etc/sysctl.conf to set net.ipv4.icmp_echo_ignore_all=1
    2. Execute sysctl -p to disable ping
  2. Use playbook sysctl module to enable ping, enabling ping would be succesful.

In this case, sysctl module changes /etc/sysctl.conf.