Apache2 server down Private key not found

Question

 AH02579: Init: Private key not found

I have

1. ubuntu
2. root

3. www-data
   users
   my root and ubuntu can access the key file

   nano /etc/letsencrypt/live/server.x.com/fullchain.pem
   

And when i do

sudo service apache2 restart

my website gave 521 and acpache logs show

AH02564: Failed to configure encrypted (?) private key$
AH00016: Configuration Failed
[Mon May 25 17:19:12.374354 2020] [ssl:error] [pid 4962:tid 140701433358208] AH02579: Init: Private key not found

I have done

sudo chmod 700 /etc/letsencrypt/live/server.x.com/
sudo chmod 400 /etc/letsencrypt/live/server.x.com/fullchain.pem

But still apache can not find key

---

Update

Hey i think this is something that can help answering
I do have 2 pem files
And when i go to previous private key and do

ubuntu@ip-172:/etc/letsencrypt/live/app.x.com$ openssl rsa -in privkey.pem -noout -check
RSA key ok

and if i use this then server is running fine
But when i add my other subdomain and created certificate for it then

ubuntu@ip-172:/etc/letsencrypt/live/server.x.com$ openssl rsa -in privkey.pem -noout -check
Error opening Private Key privkey.pem
140659156387480:error:0200100D:system library:fopen:Permission denied:bss_file.c:398:fopen('privkey.pem','r')
140659156387480:error:20074002:BIO routines:FILE_CTRL:system lib:bss_file.c:400:
unable to load Private Key

And when i load this in.conf file then apache2 give error

---

   ubuntu@ip-172:/etc/letsencrypt/live/server.x.com$ openssl req -x509 -newkey rsa:4096 -keyout key.pem -out cert.pem -days 365

After running this command

  Generating a 4096 bit RSA private key
    ...........................................................................................................................................................................................................................................................................++
    ..........++
    unable to write 'random state'
    writing new private key to 'key.pem'
    Enter PEM pass phrase:
    Verifying - Enter PEM pass phrase:
    -----
    You are about to be asked to enter information that will be incorporated
    into your certificate request.
    What you are about to enter is what is called a Distinguished Name or a DN.
    There are quite a few fields but you can leave some blank
    For some fields there will be a default value,
    If you enter '.', the field will be left blank.
    -----
    Country Name (2 letter code) [AU]:IN
    State or Province Name (full name) [Some-State]:X
    Locality Name (eg, city) []:Phillaur
    Organization Name (eg, company) [Internet Widgits Pty Ltd]:      
    Organizational Unit Name (eg, section) []:server
    Common Name (e.g. server FQDN or YOUR name) []:rajanlagah
    Email Address []:rajanlagah@gmail.com

And

ls
cert.pem  key.pem

And

ubuntu@ip-172:/etc/letsencrypt/live/server.x.com$ openssl rsa -in cert.pem 
unable to load Private Key
140670293214872:error:0906D06C:PEM routines:PEM_read_bio:no start line:pem_lib.c:701:Expecting: ANY PRIVATE KEY

Answer 1

Check if SSLCertificateKeyFile is pointing to a file containing a private key.ie

# openssl rsa -in /opt/localhost.key -noout -check
RSA key ok

create a self sign certificate using openssl req -x509 -newkey rsa:4096 -keyout key.pem -out cert.pem -days 365 .