Changed my Server ssh_config and now Putty displays black screen with green box: What do I do?

Question

My hosting service sent me this link to follow to prevent future brute force attacks on my VPS. I changed the port from 22 to 899, changed my deny file with

sshd: ALL

then added sshd : 11.22.33.44 in my allow file changing the address with my own (both home and work on one line). I added AllowedUsers but deleted it after. I then ran the semanage command to allow the new port on my CentOs 7 OS and updated and restarted the ssh service ( in fact when I run a certan command (can't remember which, the 899 is shown as working.) I can get into my server through VNC from the host using root and password, but Putty just displays a black screen with green box. I did change Putty to use the new port, but my keys are the same.

I am pretty new to the server game but have been reading up heavily on it. I am just trying to prevent the 1000s of foreign login attempts so I can get to my forte of python programming. Any advice on how to fix this is super appreciated!

score 0 · Answer 1 · edited Jun 11 '20 at 10:02

0

Did you add the 899/tcp to firewalld/iptables?

sudo firewall-cmd --zone=public --permanent --add-port=899/tcp

sudo firewall-cmd --reload

Also try without selinux enabled

setenforce 0

edited Jun 11 '20 at 10:02

Community

1

answered Apr 24 '19 at 19:54

gixnex

143
10

yes, but i will try this again to make sure – user520726 Apr 24 '19 at 20:21
nope to the setenforce – user520726 Apr 24 '19 at 21:23
Don't change rules with `--permanent` and then reload the firewall. If you make a mistake, you could lock yourself out permanently. You should add the rule first, and then make it permanent only if it works properly. – Michael Hampton Apr 25 '19 at 02:22

score 0 · Answer 2 · answered Apr 25 '19 at 01:23

0

Found out the answer. I had switched my zones in firewall-cmd without adding the needed services!

answered Apr 25 '19 at 01:23

user520726

11
2

Changed my Server ssh_config and now Putty displays black screen with green box: What do I do?

2 Answers2