NTP
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Nous devons déployer un serveur NTP local.
Ce dernier doit distribuer l'heure obtenue auprès d'une source fiable et ne doit pas être modifiable par les clients.
Solution proposée
Le serveur NTP répond à ce besoin.
Nous allons l'implémenter sur la machine responsable du DHCP.
Implémentation
Installation:
ntp.conf
Modifications effectuées par rapport à la configuration par défaut:
- Ajout du serveur ntp.uvsq.fr
- Broadcast configurée sur 192.169.255.255
- Désactivation des pools (on fait confiance au NTP de notre fac :smile:)
| /etc/ntp.conf |
|---|
| # /etc/ntp.conf, configuration for ntpd; see ntp.conf(5) for help
driftfile /var/lib/ntp/ntp.drift
# Leap seconds definition provided by tzdata
leapfile /usr/share/zoneinfo/leap-seconds.list
# Enable this if you want statistics to be logged.
#statsdir /var/log/ntpstats/
statistics loopstats peerstats clockstats
filegen loopstats file loopstats type day enable
filegen peerstats file peerstats type day enable
filegen clockstats file clockstats type day enable
# You do need to talk to an NTP server or two (or three).
server ntp.uvsq.fr
# pool.ntp.org maps to about 1000 low-stratum NTP servers. Your server will
# pick a different set every time it starts up. Please consider joining the
# pool: <http://www.pool.ntp.org/join.html>
#pool 0.debian.pool.ntp.org iburst
#pool 1.debian.pool.ntp.org iburst
#pool 2.debian.pool.ntp.org iburst
#pool 3.debian.pool.ntp.org iburst
# Access control configuration; see /usr/share/doc/ntp-doc/html/accopt.html for
# details. The web page <http://support.ntp.org/bin/view/Support/AccessRestrictions>
# might also be helpful.
#
# Note that "restrict" applies to both servers and clients, so a configuration
# that might be intended to block requests from certain clients could also end
# up blocking replies from your own upstream servers.
# By default, exchange time with everybody, but don't allow configuration.
restrict -4 default kod notrap nomodify nopeer noquery limited
restrict -6 default kod notrap nomodify nopeer noquery limited
# Local users may interrogate the ntp server more closely.
restrict 127.0.0.1
restrict ::1
# Needed for adding pool entries
#restrict source notrap nomodify noquery
# Clients from this (example!) subnet have unlimited access, but only if
# cryptographically authenticated.
#restrict 192.168.123.0 mask 255.255.255.0 notrust
# If you want to provide time to your local subnet, change the next line.
# (Again, the address is an example only.)
broadcast 192.169.255.255
# If you want to listen to time broadcasts on your local subnet, de-comment the
# next lines. Please do this only if you trust everybody on the network!
#disable auth
#broadcastclient
|
Redémarrage du service pour prendre les modifications en compte:
Sources