mahen3d's questions

I have below crontab in the system (Centos 7.9), However i am unable to verify if this runs correctly or not,

i.e if the crontab finds the PHP enr. variables or if the crontab has executed correctly without any errors in the shell or if the crontab entry has syntax issue ..etc

Any suggestion on how to do debug or capturing the output of a crontab like this one below

0 */1 * * * /var/www/example.com/scripts/cron.sh >> /var/log/app/cron/cron.log

Script content is like below

[root@]# cat /var/www/example.com/scripts/cron.sh
#!/usr/bin/env bash

cd /var/www/example.com/public
php cron.php 

Is there better way to do this?

Can someone explain to me what is the meaning of "2>&1" doing here in the below cron job

0 23 * * * wget -q -O /dev/null "https://example.com/index.php" > /dev/null 2>&1

My System environment, is Centos-7.9, Apache2.4, Php-fpm, PHP-7.4

I have postfix setup to send emails from the website, which is working in stand-alone test emails and when I turn the SELinux off.

However, if SELinux is enabled it will block sending the emails out from the server with below error in the /var/log/maillog

 postfix/sendmail[10883]: fatal: execv /usr/libexec/postfix/smtpd: Permission denied

When i do

  sudo setenforce 0

It sends emails, however, I don't want to turn SELinux off, But i would like to allow my Web-Application to white-list sending emails. I tried below but that didn't work

sudo setsebool -P httpd_can_sendmail 1

Any idea on how to solve this issue?

I have a simple question, however, I am struggling to understand how to do this in a secure manner,

I have a PHP-based web application that runs on Linux (Centos7), I have "user" access with Sudo privilege on the Linux server.

The web server (Apache) runs as an "apache" user with an "apache" group,

The problem is when I try to deploy applications using WinSCP, I get permission denied errors, the ONLY way I can solve this problem is to do a

usermod -g apache myusername
chmod 775 /var/www/html

I don't want to give 775 to the entire web folder, I think it's a big security issue, What is the most secure way to archive this type of task?

How can I deploy my app using Winscp with my user account but AS apache user? or any other suggestions on common industry practice that is considered safe?

When i do a Centos 8 routine update from below command.

dnf update

I got a below error, i have no idea on how to fix this, Any guidance on how to fix this will very valuable.

  Running scriptlet: kernel-core-4.18.0-305.3.1.el8.x86_64                                                                                                                            528/529
dracut-install: ERROR: installing 'sgdisk'
dracut: FAILED: /usr/lib/dracut/dracut-install -D /var/tmp/dracut.RTu0To/initramfs -a sgdisk

When i try to install PHP with Remi repository i get the below error

         dnf module list php
        Remi's Modular repository for Enterprise Linux 8 - aarch64   
        Errors during downloading metadata for repository 'remi-modular':
          - Status code: 403 for http://cdn.remirepo.net/enterprise/8/modular/aarch64/mirror (IP: 176.31.103.194)
          - Status code: 403 for http://cdn.remirepo.net/enterprise/8/modular/aarch64/mirror (IP: 195.154.241.117)
        Error: Failed to download metadata for repo 'remi-modular': 
    Cannot prepare internal mirrorlist: Status code: 403 for
http://cdn.remirepo.net/enterprise/8/modular/aarch64/mirror (IP: 176.31.103.194)

If visit the page not found i get an error called

Only mirrorlist are served. Use https://rpms.remirepo.net/ for content.

Below is how i installed the Remi

dnf install https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm
yum update
dnf install https://rpms.remirepo.net/enterprise/remi-release-8.rpm

I am trying to see, what is the web-server name of a particular website.

http://browserspy.dk/webserver.php

When I searched I got response as

Server: cloudflare-nginx

I know nginx and cloud-flare but I never heard a web-server named cloudflare-nginx.

Usually I get "nginx" as the webserver if website is powered by "nginx"

Can someone explain this Server: cloudflare-nginx means ?

I would like to know whether there is something like apache mod_status for nginx web server as well, basically i want to know all the requests that are currently processing by nginx process..

is this possible ?

What is the meaning of the tilde after the location block in the nginx configuration?

for example

location ~ ^/download/(.*)$ {
  alias /home/website/files/$1;
}

What is the difference between with and without the "~" ?

What is the main difference between yum remi and yum atomic repository ?

I have problem as i have installed them both and now they are conflicting in the

Yum update

I think they both serves the same set of packages isn't it ? what is the most suitable packages to use in a web-server ? and how to get rid of one of these repository ?

I think i have epel repository as well (which i think is the base repo for yum) isn't it ?

please help i am a new bee for the linux centos 6.4

in my php coding i have following line which uses by SWIFT MAILER Class

if(!stream_socket_enable_crypto($this->smtp_conn, true, STREAM_CRYPTO_METHOD_TLS_CLIENT)) {

  return false;

}

however rarely (not always) i get following php error

stream_socket_enable_crypto(): SSL operation failed with code 1. OpenSSL Error messages:
error:1408F10B:SSL routines:SSL3_GET_RECORD:wrong version number

i am not sure where the problem is or should i ignore this as this happens only once in a while

I have many error log entries called

 ServerContext: 1 leaked_rewrite_drivers on destruction

AND

child process 10494 still did not exit, sending a SIGTERM

does anyone has any idea on how to fix these errors ?

I am trying to detect which version of the java is running in my system (i mean i want to find out whether my java installation is 32 bit or 64 bit)

I have tried

$java -version 

which outputs following

java version "1.6.0_24"
OpenJDK Runtime Environment (IcedTea6 1.11.11.90)
(rhel-1.62.1.11.11.90.el6_4-x86_64)
OpenJDK 64-Bit Server VM (build 20.0-b12, mixed mode)

1. is this java 64bit install ?
2. is this means java VM is running 64 bit or can it run on both mode ?
3. If i has to install java 64 version as well, and setup the JAVA_HOME var to that path how to do this ?
4. Long time ago (10 years ago) i did learn java, but those days we didnt had anything called java server like above, is this something different to normal JVM those days ?
5. is in Centos can we run java as a Service ?

anyone who can help me, really appreciated.

My question is there any advantage using nginx as reverse proxy when most of the content is dynamically generated via php ?

As far as i am concern the nginx is very useful in caching the static content into a cache and serving the multiple requests at once ..

is this true ? or is there any other advantages of the running nginx as a reverse proxy in mostly php driven dynamic content websites ?

I have website, which is a very popular website, but from last two weeks several customers complain to me that my site was hacked and redirected to a porn website,

but whenever i check the website i cant see anything like that, users says they sometimes redirected to a porn website and then just in split of a second its gone and correct website appears.

This is very annoying for me, as far as i am concern my DNS setup is fine, (i confirmed this with my server hosting also)

what the possibilities/reason of this type of a thing happening ?

is this our server security problem ?

OR is this a someone hacked into a a ISP and change the DNS records for my site and of some of my customers which uses that ISP are experiencing this problem? (i never experience this problem myself)

is there a set of DNS checks i can do to verify it works ?

or Will this be a DNS problem or something else ... i am clueless

I just want to know why people say eAccelerator won't work if SuPHP is enabled, because in my server I was running e-accelerator and now i have enabled suphp and it seems to be working fine so far at least ...

Questions are

1. is this a good idea to run both ?
2. if i am to disable the e-accelerator how do i do that ?
3. is there any alternative to do acceleration other than the e-accelerator when using suphp ?
4. What the tips for making the webserver fast with php ?
5. Any idea of the performance and recommendation of the XCache opcode ?

I have a webserver, i need to check number of connections in my server at that given time,

i used following

netstat -anp |grep 80 |wc -l

this returned with

2542

but from my google analytics's i know that simultaneous users is not more than 100.

is this correct ? 
if not how to i get the active number of connections ? 
is this sign of a victim of DOS attack how do i know that ?

I have pretty good web (dedicated) server with good memory resources:

System information
Server load     2.19 (8 CPUs)   
Memory Used     29.53% (4,804,144 of 16,267,652)    
Swap Used   10.52% (220,612 of 2,097,136)   

As you can see, my server is using swap when there is plenty of free memory available.

Is this normal or is there something wrong with the configuration or the coding ?

N.B.
My MySQL process is using over 160% of the CPU power for some reason; I don't know why, but I don't have more than 70 simultaneous users ...

For some domains nslookup gives me a Non-authoritative answer section. What does this mean?

Got answer:
    HEADER:
        opcode = QUERY, id = 3, rcode = NXDOMAIN
        header flags:  response, want recursion, recursion avail.
        questions = 1,  answers = 0,  authority records = 1,  additional =

    QUESTIONS:
        www.example.com.SME, type = AAAA, class = IN
    AUTHORITY RECORDS:
    ->  (root)
        ttl = 1787 (29 mins 47 secs)
        primary name server = a.root-servers.net
        responsible mail addr = nstld.verisign-grs.com

------------
Non-authoritative answer:
------------

------------
Name:    example.com
Address:  93.184.216.34
Aliases:  www.example.com

Is there a easy way for me to:

• search for a string in the output window of the putty ?
• or even a Linux command to search and highlight a string in the output ?

I have 20,000+ lines in the output and sometimes I have to search for customer_id : 1111 and currently I have to copy them to word or notepad and then search.

Is there a better way to do this ?