stratum 1 ntp servers

Linux NTP server-side configuration:1) Setting the/etc/ntp.conf configuration file[Email protected] etc]# vi/etc/ntp.conf# For more information on this file, see the "the Man pages"# ntp.conf (5), NTP_ACC (5), Ntp_auth (5), Ntp_clock (5), Ntp_misc (5), Ntp_mon (5).Driftfile/var/lib/ntp/drift# Permit time synchronization with We time source, but does not# permit t

Ntp:network Time Protocol is a protocol used to synchronize the timing of a computer, which allows the computer to synchronize its server or clock source (such as a quartz clock, GPS, and so on) to provide a high-precision time correction (less than 1 milliseconds between the LAN and the standard difference, Dozens of MS on the WAN), and can be referred to as a cryptographic acknowledgment to prevent malicious protocol attacks.

/ntp.confRestrict 127.0.0.1Restrict-6:: 1Restrict 192.168.1.0 mask 255.255.255.0 # allow access to 192.168.1.0 network segmentsServer 127.127.1.0 # Local Clock addressFudge 127.127.1.0 Stratum Local 127.127.1.0 is 10th floor6. Restart ntpd Service[Email protected] ~]#/etc/init.d/ntpd restartClose ntpd: [Failed]Starting ntpd: [OK]7. Test:Before testing, to detect whether the firewall, SELinux are off!!! Service side:[[Email protected] ~]# Date

: 0.003906 (SEC)Auth delay: 0.000122 (SEC)System flags: bclient PLL monitor filegenSystem uptime: 578 (SEC)Clock stability: 1988.000000 (SEC)Clock frequency: 15904.000000 (SEC)Peer: 120.4.8.1Flags: (configured) (sys peer)Stratum: 11, version: 3Our mode: client, his mode: ServerSubsystem group PID statusXntpd TCPIP 6029448 active You can use the ntpdate clock source ip command to synchronize the clock in real time This article is from the "mo

When a program runs on multiple servers, the clock on these servers is sometimes the same. However, when the server runs for a certain period of time, the clock on each server may be different, in this case, all servers need to automatically calibrate their respective clocks. NTP is a convenient clock service, which ca

does not have other services related to foreign IP addresses, which is suspicious. I tried to stop the NTP service first, and the network adapter outgoing traffic immediately dropped to a normal level. The problem is found. The cause is unknown. I tried to ask other people and found that there are many attacks recently, collectively referred to as "NTP reflection amplification attack". Its principle is:

BKJIA exclusive Article] how to optimize your Linux production server? Based on practical experience, this article summarizes nine key points for optimizing Linux production servers. If you have not used some methods, try again. I. Time Synchronization The time requirements of servers in the production environment are accurate. My email server's dovecot service often stops services automatically due to time

1. DHCP server configuration 1. Install the DHCP service package RHEL4 fourth disc, dhcp-3.0.1-12_EL.i386.rpm Mount/dev/cdrom/media/cdrom/ Install the DHCP package Rpm-ivh/media/cdrom/RedHat/RPMS/dhcp-3.0.1-12_EL.i386.rpm 2. dhcp. conf configuration file parsing Copy the sample file to/etc/ Cp/usr/share/doc/dhcp-3.0.1/dhcpd. conf. sample/etc/dhcpd. conf Configure an instance Ddns-update-style interim; Ignor