как установить Linux phat клиент для подключения vpn сервера от машины человечности?

Ваш первый шаг должен осмотреть install_linux_phat_client.sh и посмотрите, как это решает выпустить то сообщение об ошибке.

Однако на МОЕМ YMMV Ubuntu 16.04.5:

walt@bat:~(0)$ dpkg -l libnss*
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name                                    Version                  Architecture             Description
+++-=======================================-========================-========================-====================================================================================
un  libnss-db                               <none>                   <none>                   (no description available)
ii  libnss-mdns:amd64                       0.10-7                   amd64                    NSS module for Multicast DNS name resolution
ii  libnss3:amd64                           2:3.28.4-0ubuntu0.16.04. amd64                    Network Security Service libraries
ii  libnss3-1d:amd64                        2:3.28.4-0ubuntu0.16.04. amd64                    Network Security Service libraries - transitional package
ii  libnss3-nssdb                           2:3.28.4-0ubuntu0.16.04. all                      Network Security Security libraries - shared databases
walt@bat:~(0)$ apt-cache search libnss
libnss-db - NSS module for using Berkeley Databases as a naming service
libnss-extrausers - nss module to have an additional passwd, shadow and group file
libnss-mdns - NSS module for Multicast DNS name resolution
libnss-myhostname - nss module providing fallback resolution for the current hostname
libnss-sss - Nss library for the System Security Services Daemon
libnss3 - Network Security Service libraries
libnss3-1d - Network Security Service libraries - transitional package
libnss3-dbg - Debugging symbols for the Network Security Service libraries
libnss3-dev - Development files for the Network Security Service libraries
libnss3-nssdb - Network Security Security libraries - shared databases
winbind - service to resolve user and group information from Windows NT servers
libnss-cache - NSS module for using nsscache-generated files
libnss-docker - nss module for finding Docker containers
libnss-gw-name - nss module that names the current gateway’s IP address
libnss-ldap - NSS module for using LDAP as a naming service
libnss-ldapd - NSS module for using LDAP as a naming service
libnss-lwres - NSS module for using bind9's lwres as a naming service
libnss-mymachines - nss module to resolve hostnames for local container instances
libnss-mysql-bg - NSS module for using MySQL as a naming service
libnss-pgsql2 - NSS module for using PostgreSQL as a naming service
libnss-rainbow2 - nss library for rainbow
libnss-resolve - nss module to resolve names via systemd-resolved
libnss-rsbac2 - RSBAC NSS module
libnss-securepass - NSS (Name Service Switch) module for Securepass
libnss-winbind - Samba nameservice integration plugins
libnss-wrapper - NSS wrapper library
libnss3-tools - Network Security Service tools
libpam-ccreds - Pam module to cache authentication credentials
libpam-ldap - Pluggable Authentication Module for LDAP
nslcd - daemon for NSS and PAM lookups using LDAP
nss-passwords - read passwords from a Mozilla keyring
nss-updatedb - Cache name service directories in DB format
nsscache - asynchronously synchronise local NSS databases with remote directory services
pynslcd - daemon for NSS and PAM lookups via LDAP - Python version
python-libsss-nss-idmap - Python bindings for the SID lookups library
python3-libsss-nss-idmap - Python3 bindings for the SID lookups library

Я предлагаю, чтобы Вы установили libnss3 пакет.

@gopi-nathan После проверки файла я нашел, что это пытается:

if [ -a $FIREFOX_DEB_ARCH -o -a $FIREFOX_RHEL_ARCH ] ; then
    echo "NSS libs available"
else
    echo "NSS library is not available .. exiting"
    exit 1
fi

Где:

FIREFOX_DEB_ARCH=/usr/lib/firefox/firefox
FIREFOX_RHEL_ARCH=/usr/lib64/firefox/firefox

Тем не менее можно сделать: sudo apt install firefox

Вы должны использовать терминал, чтобы распаковать установщик и запустить его:

tar -zxf linux_phat_client.tgz
cd linux_phat_client
sudo ./install_linux_phat_client.sh

и использовать для запуска без sudo:

./gui/naclient.sh