SSH access works, but "The connection was reset" on ipV4 Public in browser

Hello, if you checked the security groups then the connectivity is ok, you should check if in your ec2 instance is running a web server (i.e. apache).

First you can login with putty in your ec2 and run the following command
netstat -na | grep 80
if the command doesn't respond you should enbale or install a web server

You can install apache with the following commands:
sudo yum install httpd -y
then copy your index.html in /var/www/html/index.html
systemctl start httpd
systemctl enable httpd

Can you try and give me a feedback about the result?
Thanks

Thank you @andreacavallieri for your assistance !

Using Mac Terminal, the netstat -na | grep 80 command did respond as follows:

udp6 0 0 fe80::fb:3eff:fe6b::546 :::*
unix 2 [ ACC ] STREAM LISTENING 9080 /run/systemd/journal/stdout
unix 3 [ ] STREAM CONNECTED 14880

Also got the following using yum info httpd

Loaded plugins: extras_suggestions, langpacks, priorities, update-motd
Available Packages
Name : httpd
Arch : x86_64
Version : 2.4.39
Release : 1.amzn2.0.1
Size : 1.3 M
Repo : amzn2-core/2/x86_64
Summary : Apache HTTP Server
URL : https://httpd.apache.org/
License : ASL 2.0
Description : The Apache HTTP Server is a powerful, efficient, and extensible
: web server.

However, the httpd -V command yielded:
-bash: httpd: command not found

And rpm -qf /etc/httpd gave:
error: file /etc/httpd: No such file or directory

So I went ahead and installed Apache using sudo yum install httpd -y

That was successful.

Copied index.html to /var/www/html/

Then ran the following commands with the following results:

systemctl start httpd
Failed to start httpd.service: The name org.freedesktop.PolicyKit1 was not provided by any .service files
See system logs and 'systemctl status httpd.service' for details.

systemctl status httpd.service
httpd.service - The Apache HTTP Server
Loaded: loaded (/usr/lib/systemd/system/httpd.service; disabled; vendor preset: disabled)
Active: inactive (dead)
Docs: man:httpd.service(8)

systemctl enable httpd
Failed to execute operation: The name org.freedesktop.PolicyKit1 was not provided by any .service files

systemctl status httpd.service
httpd.service - The Apache HTTP Server
Loaded: loaded (/usr/lib/systemd/system/httpd.service; disabled; vendor preset: disabled)
Active: inactive (dead)
Docs: man:httpd.service(8)

httpd -v
Server version: Apache/2.4.39 ()
Server built: Apr 4 2019 18:09:28

Installed policykit using sudo install polkit

systemctl enable httpd
Asked for a password, and authentication failed as shown below:

==== AUTHENTICATING FOR org.freedesktop.systemd1.manage-unit-files ===
Authentication is required to manage system service or unit files.
Authenticating as: EC2 Default User (ec2-user)
Password:
polkit-agent-helper-1: pam_authenticate failed: Authentication failure
==== AUTHENTICATION FAILED ===
Failed to execute operation: Access denied

sudo got around the password problem:
sudo systemctl enable httpd
Created symlink from /etc/systemd/system/multi-user.target.wants/httpd.service to /usr/lib/systemd/system/httpd.service.

And it would now appear that the web server is enabled though "dead".

systemctl status httpd.service
httpd.service - The Apache HTTP Server
Loaded: loaded (/usr/lib/systemd/system/httpd.service; enabled; vendor preset: disabled)
Active: inactive (dead)
Docs: man:httpd.service(8)

http://54.203.231.30/ in the browser
still resulted in "This site can’t be reached The connection was reset."

So ...

sudo service httpd start
Redirecting to /bin/systemctl start httpd.service

systemctl status httpd.service
httpd.service - The Apache HTTP Server
Loaded: loaded (/usr/lib/systemd/system/httpd.service; enabled; vendor preset: disabled)
Active: active (running) since Sun 2019-06-30 20:35:43 UTC; 14s ago
Docs: man:httpd.service(8)
Main PID: 9520 (httpd)
Status: "Total requests: 0; Idle/Busy workers 100/0;Requests/sec: 0; Bytes served/sec: 0 B/sec"
CGroup: /system.slice/httpd.service
├─9520 /usr/sbin/httpd -DFOREGROUND
├─9521 /usr/sbin/httpd -DFOREGROUND
├─9522 /usr/sbin/httpd -DFOREGROUND
├─9523 /usr/sbin/httpd -DFOREGROUND
├─9524 /usr/sbin/httpd -DFOREGROUND
└─9525 /usr/sbin/httpd -DFOREGROUND

Jun 30 20:35:43 ip-172-31-40-8.us-west-2.compute.internal systemd[1]: Starting The Apache HTTP Server...
Jun 30 20:35:43 ip-172-31-40-8.us-west-2.compute.internal systemd[1]: Started The Apache HTTP Server.

Now http://54.203.231.30/ in the browser
gives the Apache test page!

Edited by: mikeh100 on Jun 30, 2019 1:37 PM

Thank you @andreacavallieri !

It is working!!! Web page displays at http://54.203.231.30/

netstat - na | grep 80
unix 3 [ ] STREAM CONNECTED 133807
unix 3 [ ] STREAM CONNECTED 14880
unix 3 [ ] STREAM CONNECTED 133808
unix 2 [ ] DGRAM 133801

ps -ef |grep httpd
root 9520 1 0 20:35 ? 00:00:00 /usr/sbin/httpd -DFOREGROUND
apache 9521 9520 0 20:35 ? 00:00:00 /usr/sbin/httpd -DFOREGROUND
apache 9522 9520 0 20:35 ? 00:00:00 /usr/sbin/httpd -DFOREGROUND
apache 9523 9520 0 20:35 ? 00:00:00 /usr/sbin/httpd -DFOREGROUND
apache 9524 9520 0 20:35 ? 00:00:00 /usr/sbin/httpd -DFOREGROUND
apache 9525 9520 0 20:35 ? 00:00:00 /usr/sbin/httpd -DFOREGROUND
apache 9568 9520 0 20:37 ? 00:00:00 /usr/sbin/httpd -DFOREGROUND
apache 9628 9520 0 20:45 ? 00:00:00 /usr/sbin/httpd -DFOREGROUND
ec2-user 9688 9407 0 20:57 pts/0 00:00:00 grep --color=auto httpd