How to view server configuration on CentOS?

Question

linux

So there is a server.
OS - CentOS 7
According to the documents, a DHCP server, Syslog server, Elastix -xs is running on it.
Problem: rebooted the server after installing the graph. Ghome shells - everything was done automatically, I just gave the command to install from the repository. And then all IP devices without stat. addresses fell off the network and the Internet.
After installing the static - everything worked.
BUT! When I try to look vi /etc/dhcp/dhcpd.conf configuration file DHCP - writes that it does not exist.
When you try to start the service, it goes Redirecting to /bin/systemctl start dhcpd.service.
It seems that the DHCP server did not work before, however, the server has not been rebooted for a long time (4 months).
+ IP phones that worked from DHCP also fell off - which is not at all clear, because PBX is a separate system.
Question: what to do with the DHCP server? How to see its general config - typing commands for each parameter is already tired.

Answer 1

after installing graph. Ghome shells

To the server? What for? What is the point in this step - which what the hell do everyone always pass by? 0_o
Hire an Admin.

Answer 2

You need a qualified admin, was from the very beginning, and even more so now ... Tips will not help. Getting out of you a lot of information you need to answer is a huge job, especially since you will have to give a lot of hints at every step on how to get it. It's just not realistic within a question/answer service.
Why climb there without understanding anything at all, it's just a mystery to me.
Elastics, this is probably here it is: https://www.elastix.org/
By rolling a graphical environment, you can drag a lot of extra dependencies, for example, some kind of network manager, and get a different network configuration at the output. And with this, get problems with the software configured for the old configuration.
You absolutely do not need a graphical environment on this server, besides. And if you are interested in continuing to do this, you definitely need to immediately go to the console.
Dhcpd is not the only software that can implement DHCP, and in your case it probably wasn't. elastix has DHCP management and most likely it was DHCP that worked with its forces.

Answer 3

Saenara ,
Boris Syomov ,
TyzhSysAdmin ,
Thank you all for the lack of advice and for explaining the nuances - the problem was solved by a banal yum install dhcp, that is, by reinstalling the DHCP server - a configuration file and all the required networks / settings appeared. Now I will understand the nuances.
And yes, the question about viewing the configuration of the entire server remains open.