Bug #82992 Some warnings appear in dump from mysqldump
Submitted: 14 Sep 2016 12:37 Modified: 11 Jul 2017 19:06
Reporter: Vieng Nong LO Email Updates:
Status: Closed Impact on me:
None 
Category:MySQL Server: mysqldump Command-line Client Severity:S2 (Serious)
Version:5.7.15 OS:Debian (7.11)
Assigned to: CPU Architecture:Any

[14 Sep 2016 12:37] Vieng Nong LO 
Description:
Some warning are sent to STDOUT instead of STDERR resulting of being included in the resulting dump.

Exemple of dump

WARNING: no verification of server certificate will be done. Use --ssl-mode=VERIFY_CA or VERIFY_IDENTITY.
-- MySQL dump 10.13  Distrib 5.7.15, for Linux (x86_64)
--
-- Host: ************    Database: *********
-- ------------------------------------------------------
-- Server version       5.6.16-log

WARNING: --ssl is deprecated and will be removed in a future version. Use --ssl-mode instead.
-- MySQL dump 10.13  Distrib 5.7.15, for Linux (x86_64)

The only way to remove these warnings is disabling SSL.

How to repeat:
This warning:

WARNING: no verification of server certificate will be done. Use --ssl-mode=VERIFY_CA or VERIFY_IDENTITY

is generated by this command
$MYSQLDUMP --host="$SHOST" --port="$SPORT" --compress --ssl-mode=DISABLED --ssl-ca="$CACRT" --ssl-cert="$MECRT" --ssl-key="$MEKEY" -u"$SUSER" --password="$SPASS" --add-drop-database --opt --triggers --routines $1 2>/dev/null > $TMP

This warning:

WARNING: --ssl is deprecated and will be removed in a future version. Use --ssl-mode instead.

is generated by this command
$MYSQLDUMP --host="$SHOST" --port="$SPORT" --compress --ssl=true --ssl-ca="$CACRT" --ssl-cert="$MECRT" --ssl-key="$MEKEY" -u"$SUSER" --password="$SPASS" --add-drop-database --opt --triggers --routines $1 2>/dev/null > $TMP
[11 Jan 2017 15:29] MySQL Verification Team 
Hi!

I have taken a look at the code and it turns out  that you are right.

Verified.
[11 Jul 2017 19:06] Paul DuBois 
Posted by developer:
 
Fixed in 5.7.20, 8.0.3.

Some mysqldump warnings went to the standard output rather than the
standard error output and consequently were written to the dump file.