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Outdated PHP package `php-igbinary` (`2.x`) may cause that issue `/usr/lib/php/20180731/redis.so: undefined symbol: igbinary_serialize`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