Verifying BIND releases with isc.org pgpkeys

 When it is required to verify latest releases of bind name server applications, it is required to download the isc.org latest pgp keys from https://ftp.isc.org/isc/pgpkeys/

Then follow the given procedure to verify the integrity of an ISC download using PGP.

 

1. Download the pgp key from the above given location and name the key file as 'KEYS' (Or whatever you want)

2. Download the tar.gz and Signatures file as required

3. Change the directory to the location where all public key, signature key file and tar.gz files are stored.

4. Import the public key using the PGP or GPG import option, e.g.:  gpg --import KEYS

 - Here 'KEYS' is the file which contains the public key downloaded from the key repository 

gpg --import KEYS
gpg: key 4CBB3D38: "Internet Systems Consortium, Inc. (Signing key, 2019-2020) <codesign@isc.org>" not changed
gpg: Total number processed: 1
gpg:              unchanged: 1

 

5.   Check the integrity with gpg --verify command 

Ex. 

gpg --verify bind-9.11.22.tar.gz.asc bind-9.11.22.tar.gz
gpg: Signature made 2020-08-12 01:47:02 +0530 +0530 using RSA key ID 5DACE918
gpg: Good signature from "Internet Systems Consortium, Inc. (Signing key, 2019-2020) <codesign@isc.org>"
gpg: WARNING: This key is not certified with a trusted signature!
gpg:          There is no indication that the signature belongs to the owner.
Primary key fingerprint: AE3F AC79 6711 EC59 FC00  7AA4 74BB 6B9A 4CBB 3D38
     Subkey fingerprint: 95CE DA25 6B1C A0A1 5F30  2FB5 9521 A7ED 5DAC E918

Good Reference:

https://kb.isc.org/docs/aa-01225

Getting the table list with sizes in MySQL

We may need to get the table sizes of the tables in a mysql database from the mysql command prompt.

SELECT   TABLE_NAME AS `Table`,   ROUND((DATA_LENGTH + INDEX_LENGTH) / 1024 ) AS `Size (KB)` FROM   information_schema.TABLES WHERE   TABLE_SCHEMA = "<database_name>" ORDER BY   (DATA_LENGTH + INDEX_LENGTH) DESC;

Here <database_name> needs to be changed to your database name. Also you can get the sizes in MB or GB by adding /1024 required times. For example, to get the size in MB the code has to be changed as follows;

SELECT   TABLE_NAME AS `Table`,   ROUND((DATA_LENGTH + INDEX_LENGTH) / 1024/1024) AS `Size (MB)` FROM   information_schema.TABLES WHERE   TABLE_SCHEMA = "<database_name>" ORDER BY   (DATA_LENGTH + INDEX_LENGTH) DESC

Good Reference:

https://chartio.com/resources/tutorials/how-to-get-the-size-of-a-table-in-mysql/
 

Dovecot issue in InBOX - CentOS7 Dovecot

I was configuring a mail server in CentOS7 environment with Postfix and Dovecot. When configuring Dovecot to deliver mails to the users, I noticed the following error in the mail log and user was not able to get mails in the INBOX.

dovecot: pop3(<user>@<domain>): namespace configuration error: inbox=yes namespace missing top=0/0, retr=0/0, del=0/0, size=0

According to the reviews, the error was with the name space definitions in /etc/dovecot/conf.d/15-mailboxes.conf where inbox was not enabled. I have added inbox=yes under the namespace inbox{ definition.

Please find the added line in the below content

namespace inbox {
  inbox=yes #This line was added
  # These mailboxes are widely used and could perhaps be created automatically:
  mailbox Drafts {
    special_use = \Drafts
  }
  mailbox Junk {
    special_use = \Junk
  }
  mailbox Trash {
    special_use = \Trash
  }

 Good Reference:

https://dwaves.org/2018/08/14/centos7-dovecot-exim-error-user-userdomain-com-initialization-failed-namespace-configuration-error-inboxyes-namespace-missing-error-invalid-user-settings/