首先

Debian8已默认安装了PHP-FPM5.6。
原文章：PHP、PHP-FPM的各种安装方法和EOL总结。

记录

安装

# cat /etc/os-release
PRETTY_NAME="Debian GNU/Linux 8 (jessie)"
NAME="Debian GNU/Linux"
VERSION_ID="8"
VERSION="8 (jessie)"
ID=debian
HOME_URL="http://www.debian.org/"
SUPPORT_URL="http://www.debian.org/support"
BUG_REPORT_URL="https://bugs.debian.org/"

# apt update -y;apt install -y php5-fpm
... 略

确认的种类。

# which php5
/usr/bin/php5

# which php5-fpm
/usr/sbin/php5-fpm

# php5 -v
PHP 5.6.40-0+deb8u6 (cli) (built: Sep 15 2019 11:18:30)
Copyright (c) 1997-2016 The PHP Group
Zend Engine v2.6.0, Copyright (c) 1998-2016 Zend Technologies
    with Zend OPcache v7.0.6-dev, Copyright (c) 1999-2016, by Zend Technologies

# php5-fpm -v
PHP 5.6.40-0+deb8u6 (fpm-fcgi) (built: Sep 15 2019 11:23:43)
Copyright (c) 1997-2016 The PHP Group
Zend Engine v2.6.0, Copyright (c) 1998-2016 Zend Technologies
    with Zend OPcache v7.0.6-dev, Copyright (c) 1999-2016, by Zend Technologies

# apt show php5-fpm
Package: php5-fpm
Source: php5
Version: 5.6.40+dfsg-0+deb8u6
Installed-Size: 9286 kB
Maintainer: Debian PHP Maintainers <pkg-php-maint@lists.alioth.debian.org>
Depends: libapparmor1 (>= 2.7.0~beta1+bzr1772), libbz2-1.0, libc6 (>= 2.15), libcomerr2 (>= 1.01), libdb5.3, libgssapi-krb5-2 (>= 1.6.dfsg.2), libk5crypto3 (>= 1.6.dfsg.2), libkrb5-3 (>= 1.6.dfsg.2), libonig2 (>= 5.9.5), libpcre3 (>= 1:8.35), libqdbm14 (>= 1.8.74), libssl1.0.0 (>= 1.0.1), libsystemd0, libxml2 (>= 2.9.0), zlib1g (>= 1:1.1.4), init-system-helpers (>= 1.18~), mime-support, php5-common (= 5.6.40+dfsg-0+deb8u6), php5-cli, php5-json, libmagic1, ucf, tzdata
Suggests: php-pear
Homepage: https://secure.php.net/
Section: php
Priority: optional
Download-Size: 2213 kB
APT-Manual-Installed: yes
APT-Sources: http://security.debian.org/debian-security/ jessie/updates/main amd64 Packages
Description: server-side, HTML-embedded scripting language (FPM-CGI binary)

N: There is 1 additional record. Please use the '-a' switch to see it


# apt show php5-fpm -a
Package: php5-fpm
Source: php5
Version: 5.6.40+dfsg-0+deb8u6
Installed-Size: 9286 kB
Maintainer: Debian PHP Maintainers <pkg-php-maint@lists.alioth.debian.org>
Depends: libapparmor1 (>= 2.7.0~beta1+bzr1772), libbz2-1.0, libc6 (>= 2.15), libcomerr2 (>= 1.01), libdb5.3, libgssapi-krb5-2 (>= 1.6.dfsg.2), libk5crypto3 (>= 1.6.dfsg.2), libkrb5-3 (>= 1.6.dfsg.2), libonig2 (>= 5.9.5), libpcre3 (>= 1:8.35), libqdbm14 (>= 1.8.74), libssl1.0.0 (>= 1.0.1), libsystemd0, libxml2 (>= 2.9.0), zlib1g (>= 1:1.1.4), init-system-helpers (>= 1.18~), mime-support, php5-common (= 5.6.40+dfsg-0+deb8u6), php5-cli, php5-json, libmagic1, ucf, tzdata
Suggests: php-pear
Homepage: https://secure.php.net/
Section: php
Priority: optional
Download-Size: 2213 kB
APT-Manual-Installed: yes
APT-Sources: http://security.debian.org/debian-security/ jessie/updates/main amd64 Packages
Description: server-side, HTML-embedded scripting language (FPM-CGI binary)

Package: php5-fpm
Source: php5
Version: 5.6.33+dfsg-0+deb8u1
Installed-Size: 9286 kB
Maintainer: Debian PHP Maintainers <pkg-php-maint@lists.alioth.debian.org>
Depends: libapparmor1 (>= 2.7.0~beta1+bzr1772), libbz2-1.0, libc6 (>= 2.15), libcomerr2 (>= 1.01), libdb5.3, libgssapi-krb5-2 (>= 1.6.dfsg.2), libk5crypto3 (>= 1.6.dfsg.2), libkrb5-3 (>= 1.6.dfsg.2), libonig2 (>= 5.9.5), libpcre3 (>= 1:8.35), libqdbm14 (>= 1.8.74), libssl1.0.0 (>= 1.0.1), libsystemd0, libxml2 (>= 2.9.0), zlib1g (>= 1:1.1.4), init-system-helpers (>= 1.18~), mime-support, php5-common (= 5.6.33+dfsg-0+deb8u1), php5-cli, php5-json, libmagic1, ucf, tzdata
Suggests: php-pear
Homepage: https://secure.php.net/
Tag: devel::interpreter, devel::lang:php, devel::web, implemented-in::c,
 role::shared-lib, secteam::squeeze-limited-support,
 secteam::wheezy-limited-support, web::scripting
Section: php
Priority: optional
Download-Size: 2213 kB
APT-Sources: http://deb.debian.org/debian/ jessie/main amd64 Packages
Description: server-side, HTML-embedded scripting language (FPM-CGI binary)