php缺少gd库

1.查看php库：

php -m

root@SAFEHOSTNAME:~# php -m
[PHP Modules]
calendar
Core
ctype
date
exif
fileinfo
filter
ftp
gettext
hash
iconv
json
libxml
mysqli
mysqlnd
openssl
pcntl
pcre
PDO
pdo_mysql
Phar
posix
readline
Reflection
session
shmop
sockets
sodium
SPL
standard
sysvmsg
sysvsem
sysvshm
tokenizer
Zend OPcache
zlib

[Zend Modules]
Zend OPcache

2.查看php版本

php -v
PHP 7.3.11-1~deb10u1 (cli) (built: Oct 26 2019 14:14:18) ( NTS )
Copyright (c) 1997-2018 The PHP Group
Zend Engine v3.3.11, Copyright (c) 1998-2018 Zend Technologies
    with Zend OPcache v7.3.11-1~deb10u1, Copyright (c) 1999-2018, by Zend Technologies

3.搜索库

root@SAFEHOSTNAME:~# apt-cache search php-gd
php-gd - GD module for PHP [default]
php7.3-gd - GD module for PHP

4.安装对应的gd库

apt-get install php7.3-gd
// 可选 apt-get update

5.再次查看安装的库

php -m

此时应该能看到gd了