CentOS7 Machine will not respond to ping or ssh

Question

I have two files. File X is:

module A
    module B    
        XYZ = "5"    
        def testx
            puts "Test"
        end
    end
end

File Y is as follows:

require_relative "./B/X"

def test
 puts A::B::XYZ
 puts A::B.testx
end

I am trying to call testx of file X within Y, but it is not working. However, the call to constantXYZ is successful.

What am I doing wrong?

Update: File Y needs a class structure as @AlexN pointed out, and include module B, then testx can simply be called. File Y becomes as follows:

require_relative "./B/X"
    module A
       class test
       include B        
       def        
          puts self.method("testx")
       end
    end
end

Solution

All the above checks are good, but one final check solved the problem. in the /etc/hosts and the /etc/sysconfig/network-scripts/ifcfg-en9p0 files, I had accidentally typed one digit off on the IPADDR for the machine. Stupid mistake. I put a 221 instead of a 121, and 221 was also the address of a machine that was in the tables but turned off. So that explains how I could get OUT but not IN.

So for a very secure machine, tell it it has the IP of a down'ed machine and tell your DNS server it has a different address. No one will be able to get in.

Comments

[Petr Gazarov]

XYZ is called a constant, not a variable, fyi.

[M. Suurland]

@PetrGazarov thanks for the feedback, see the edit

[Deathgrip]

Have you run tcpdump on the interface while trying to ping or ssh to this machine? Are you trying to access using its IP or hostname? Both?

[billmenger]

I'll try that, and/or wireshark on the interface. It feels like the firewalld did not actually die, that is something else I will check. (by looking for the process).

[Deathgrip]

Don't forget, the firewall will start on reboots unless you systemctl disable firewalld.

[billmenger]

I have now verified that firewalld is not running after boot (disabled it and removed link). I installed iptables and set up default rules that would allow ssh and ping from anyone. selinux is disabled. tcpdump output from another workstation in the subnet shows ARP requests "IPv4 (len 4), Request who-has xxx tell yyy, length 46" when attempting to ping or ssh to the machine. GATEWAY, NETMASK, IPADDR all are good and consistent with the subnet. DNSMASQ is used to resolve names and seems to be working flawlessly. I am still stumped. Thanks @Deathgrip, appreciate the advice!

[M. Suurland]

I seem to solve it, I indeed needed to use a class structure in Y, and include model B, then I can just call testx

[M. Suurland]

Thank you for your answer, but I guess the "extend self" is then required in many classes (I have many classes like X) which makes the class solution less redundant, correct me if I am wrong :)

[Cary Swoveland]

The downvote is mine.True, this creates a class method testx, but it also creates an unwanted instance method with the same name. It's a bizarre alternative to simply creating a class method directly.

[M. Suurland]

@CarySwoveland Thanks for the comment/feedback