[systemd-devel] How to get used to systemd vs init

[Chad]

On 6/23/2015 4:45 PM, Ronny Chevalier wrote:
> On Wed, Jun 24, 2015 at 1:37 AM, Chad <ccolumbu at gmail.com> wrote:
>> Oh, wait this is the reverse of what I want/need (systemd-sysv-generator
>> goes from init.d to systemd, I need from systemd to init.d).
>> I have a nagios script that runs something like:
>> /etc/init.d/httpd status
>> It then reads the output and makes sure httpd is running, if not it takes
>> action depending on the service.
>> I use that method for tons of services.
>> I don't want to have to re-write the modules to use:
>> systemctl status httpd
>> If I did that then I will not be able to rsync the scripts/configs around
>> and would have to maintain 2 versions of the code.
>> I was wondering if there was an easy way to create a /etc/init.d/httpd
>> script that called something like this inside:
>> #!/bin/bash
>> systemctl $1 $0
>> I know it is not that simple ($0 for example is the full path
>> /etc/init.d/httpd not just the httpd), which is why I am hoping there is a
>> tool for this.
>>
> If you just want to know if a service is active you can use:
>
> systemctl is-active httpd
>
> If $? equals 0 then the service is active, else it is not :)
>
> If you make your script use this I don't see why you would have to
> maintain multiple versions, if your intention is to use systemd
> everywhere.
Except that I can not convert all servers I maintain over just like that, it will take time, probably 1-2 years.

As to: systemctl is-active httpd, that would work sometimes but not others. For example I check fail2ban by running 
/etc/init.d/iptables status which outputs all the firewall rules then check that output to make sure the chains for 
fail2ban are there. If you restart iptables without restarting fail2ban, fail2ban will show as running because the 
daemon is up, but since the chains are gone it can not ban bad guys.

Maybe one of you knows a solution to that (iptables restart without a fail2ban restart), I have not found one for 
init.d, is this fixed somehow in systemd?
That would be another advantage.

^C