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Edit File: chronyd.service

[Unit]
Description=NTP client/server
Documentation=man:chronyd(8) man:chrony.conf(5)
After=ntpdate.service sntp.service ntpd.service
Conflicts=ntpd.service systemd-timesyncd.service
ConditionCapability=CAP_SYS_TIME

[Service]
Type=forking
PIDFile=/run/chrony/chronyd.pid
EnvironmentFile=-/etc/sysconfig/chronyd
ExecStart=/usr/sbin/chronyd $OPTIONS

CapabilityBoundingSet=~CAP_AUDIT_CONTROL CAP_AUDIT_READ CAP_AUDIT_WRITE
CapabilityBoundingSet=~CAP_BLOCK_SUSPEND CAP_KILL CAP_LEASE CAP_LINUX_IMMUTABLE
CapabilityBoundingSet=~CAP_MAC_ADMIN CAP_MAC_OVERRIDE CAP_MKNOD CAP_SYS_ADMIN
CapabilityBoundingSet=~CAP_SYS_BOOT CAP_SYS_CHROOT CAP_SYS_MODULE CAP_SYS_PACCT
CapabilityBoundingSet=~CAP_SYS_PTRACE CAP_SYS_RAWIO CAP_SYS_TTY_CONFIG CAP_WAKE_ALARM
DeviceAllow=char-pps rw
DeviceAllow=char-ptp rw
DeviceAllow=char-rtc rw
DevicePolicy=closed
LockPersonality=yes
MemoryDenyWriteExecute=yes
NoNewPrivileges=yes
PrivateTmp=yes
ProtectControlGroups=yes
ProtectHome=yes
ProtectHostname=yes
ProtectKernelLogs=yes
ProtectKernelModules=yes
ProtectKernelTunables=yes
ProtectProc=invisible
ProtectSystem=full
RestrictAddressFamilies=AF_INET AF_INET6 AF_UNIX
RestrictNamespaces=yes
RestrictSUIDSGID=yes
SystemCallArchitectures=native
SystemCallFilter=~@cpu-emulation @debug @module @mount @obsolete @raw-io @reboot @swap

# Adjust restrictions for /usr/sbin/sendmail (mailonchange directive)
NoNewPrivileges=no
RestrictAddressFamilies=AF_NETLINK

[Install]
WantedBy=multi-user.target