php-redis & php-igbinary

1. Issue

+ php7.3 /usr/local/bin/composer install --ansi
 PHP Warning:  PHP Startup: Unable to load dynamic library 'redis.so' 
 (tried: /usr/lib/php/20180731/redis.so (/usr/lib/php/20180731/redis.so: undefined symbol: igbinary_serialize), 
 /usr/lib/php/20180731/redis.so.so (/usr/lib/php/20180731/redis.so.so: undefined symbol: igbinary_serialize)) 
 in Unknown on line 0

2. Solution

Outdated PHP package php-igbinary (2.x) may cause that issue /usr/lib/php/20180731/redis.so: undefined symbol: igbinary_serialize

root@home:# dpkg -l | grep php

php-igbinary                         2.0.6~rc1-1+ubuntu16.04.1+deb.sury.org+1
php-redis                            4.3.0-1+ubuntu16.04.1+deb.sury.org+1

Solution is re-install both php-redis & php-igbinary

root@home:# apt install php-redis php-igbinary
...

After that, they're working smoothly. Here is new version of php-igbinary

php-igbinary                         3.0.1+2.0.8-1+ubuntu16.04.1+deb.sury.org+1
php-redis                            4.3.0-1+ubuntu16.04.1+deb.sury.org+1