Linux KVM 物理服务器 卖VPS 虚拟化 超售 配置

KVM和OpenVZ虚拟化一样 都提供了允许超过物理内存大小的VPS配置,
很多内存分配给VPS,但是并未被完整使用,我们可以将这部分内存分配其他用户

举个例子
如果我们的物理服务器有128G内存, 不开启超售配置, 我们可以开通
128G – 4G(物理系统必要的内存) = 124G空闲内存 = 124 个 1G内存VPS

如果我们超售50%
128G – 4G(物理系统必要的内存) = 124G空闲内存 = 248 个 1G内存VPS

这也是为什么市面上基于KVM虚拟化的VPS价格越来越低的原因

目前基于KVM的超售配置,都是使用的KSM
KSM 全称是 (kernel same-page merging).
原理是将相同内容的内存页面合并, 比如我们运行了10个windows
这10个Windows内核占用的部分内存 数据是完全一样的,原来10份数据合并为一份
这样就减少了内容使用
Continue reading “Linux KVM 物理服务器 卖VPS 虚拟化 超售 配置”

Linux FTP 备份服务器部署文档

客户需求部署
4台网站服务器 1台备份服务器

需求 : 集中备份 每天/每周/每月的网站数据至独立的备份服务器

网站服务器 均采用cPanel 支持周期备份

完成后测试了一下 速度还可以 100M端口跑满

部署安装
# 编译安装ProFTPD

#设置开机启动
chkconfig proftpd on
#启动
service proftpd start

#添加备份的用户组和用户 Continue reading “Linux FTP 备份服务器部署文档”

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  • testing\\u003CScRiPt\\HhCs(9777)\\u003C/sCripT\\u003E
  • testingDIatT <ScRiPt >92a2(9387)</ScRiPt>
  • testing<img src=//testasp vulnweb com/t/dot gif onload=HhCs(9206)>
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  • testing<img<!-- --> src=x onerror=alert(9756);//><!-- -->
  • testing}body{acu:Expre/**/SSion(HhCs(9487))}
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自动Kill使用太多处理器资源的进程

#!/bin/bash

# March-13-2006
# CPUuse trigger script by Noel
#
# bash code to watch a running program’s CPU usage.
# if it’s above a set value, it will auto send an email.
# You will need to set a Cron job to run this script every xx minutes
#
# Set some needed things:
#
processToWatch=”convert” # in my case I need to watch convert
emailAddress=”root@host” # this is my main emailaddress
triggerValue=90 # if the CPU use is above 90% send an email. DO NOT USE a DOT or COMMA!
tempFileName=tmp-cpu # some name of the temp file for the ps, grep data Continue reading “自动Kill使用太多处理器资源的进程”

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Linux Route 路由表 Linux路由命令使用 操作手册!

用途说明
route命令用于显示和操作IP路由表(show / manipulate the IP routing table)。要实现两个不同的子网之间的通信,需要一台连接两个网络的路由器,或者同时位于两个网络的网关来实现。在Linux系统中,设置路由通常是为了解决以下问题:该Linux系统在一个局域网中,局域网中有一个网关,能够让机器访问Internet,那么就需要将这台机器的IP地址设置为Linux机器的默认路由。要注意的是,直接在命令行下执行route命令来添加路由,不会永久保存,当网卡重启或者机器重启之后,该路由就失效了;可以在/etc/rc.local中添加route命令来保证该路由设置永久有效。本文中的例子中会验证这一点。

常用参数
格式:route
格式:/sbin/route
用于打印路由表(display the current routing table)。
在非root用户使用时需要使用完整路径执行route命令。

格式:route -n
格式:/sbin/route -n
用于打印路由表,加上-n参数就是在输出的信息中不打印主机名而直接打印ip地址。像netstat命令也有此参数。

格式:route add default gw {IP-ADDRESS} {INTERFACE-NAME}
用于设置默认路由(adds a default route, which will be used if no other route matches),其中,
参数{IP-ADDRESS): 用于指定路由器(网关)的IP地址(Specify router IP address);
参数{INTERFACE-NAME}: 用于指定接口名称,如eth0(Specify interface name such as eth0)。使用/sbin/ifconfig -a可以显示所有接口信息。
man route 写道
route add default gw mango-gw
adds a default route (which will be used if no other route matches). All packets using this route will
be gatewayed through “mango-gw”. The device which will actually be used for that route depends on how we
can reach “mango-gw” – the static route to “mango-gw” will have to be set up before.

格式:route add -net {NETWORK-ADDRESS} netmask {NETMASK} dev {INTERFACE-NAME}
添加到指定网络的路由规则,其中
参数{NETWORK-ADDRESS}: 用于指定网络地址
参数{NETMASK}: 用于指定子网掩码
参数{INTERFACE-NAME}: 用于指定接口名称,如eth0。
man route 写道
route add -net 192.56.76.0 netmask 255.255.255.0 dev eth0
adds a route to the network 192.56.76.x via “eth0”. The Class C netmask modifier is not really necessary
here because 192.* is a Class C IP address. The word “dev” can be omitted here.

route add -net 224.0.0.0 netmask 240.0.0.0 dev eth0
This is an obscure one documented so people know how to do it. This sets all of the class D (multicast)
IP routes to go via “eth0”. This is the correct normal configuration line with a multicasting kernel.

格式:route add -net {NETWORK-ADDRESS} netmask {NETMASK} reject
设置到指定网络为不可达,避免在连接到这个网络的地址时程序过长时间的等待,直接就知道该网络不可达。
man route 写道
route add -net 10.0.0.0 netmask 255.0.0.0 reject
This installs a rejecting route for the private network “10.x.x.x.”

格式:route del -net {NETWORK-ADDRESS} netmask {NETMASK} dev {INTERFACE-NAME}
格式:route del -net {NETWORK-ADDRESS} netmask {NETMASK} reject
用于删除路由设置。参数指定的方式与route add相似。

route命令输出的路由表字段含义如下:
Destination 目标
The destination network or destination host. 目标网络或目标主机。

Gateway 网关
The gateway address or ‘*’ if none set. 网关地址,如果没有就显示星号。

Genmask 网络掩码
The netmask for the destination net; ‘255.255.255.255’ for a
host destination and ‘0.0.0.0’ for the default route.

Flags Possible flags include 标志,常用的是U和G。
U (route is up) 路由启用
H (target is a host) 目标是主机
G (use gateway) 使用网关
R (reinstate route for dynamic routing)
D (dynamically installed by daemon or redirect)
M (modified from routing daemon or redirect)
A (installed by addrconf)
C (cache entry)
! (reject route)

Metric 距离、跳数。暂无用。
The ‘distance’ to the target (usually counted in hops). It is
not used by recent kernels, but may be needed by routing dae-
mons.

Ref 不用管,恒为0。
Number of references to this route. (Not used in the Linux ker-
nel.)

Use 该路由被使用的次数,可以粗略估计通向指定网络地址的网络流量。
Count of lookups for the route. Depending on the use of -F and
-C this will be either route cache misses (-F) or hits (-C).

Iface 接口,即eth0,eth0等网络接口名
Interface to which packets for this route will be sent.

使用示例
示例一 打印当前路由表(root用户)
[root@jfht ~]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
211.103.28.0 * 255.255.255.224 U 0 0 0 eth0
192.168.1.0 * 255.255.255.0 U 0 0 0 eth1
169.254.0.0 * 255.255.0.0 U 0 0 0 eth1
default 211.103.28.1 0.0.0.0 UG 0 0 0 eth0
[root@jfht ~]# /sbin/route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
211.103.28.0 * 255.255.255.224 U 0 0 0 eth0
192.168.1.0 * 255.255.255.0 U 0 0 0 eth1
169.254.0.0 * 255.255.0.0 U 0 0 0 eth1
default 211.103.28.1 0.0.0.0 UG 0 0 0 eth0
[root@jfht ~]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
211.103.28.0 0.0.0.0 255.255.255.224 U 0 0 0 eth0
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1
169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth1
0.0.0.0 211.103.28.1 0.0.0.0 UG 0 0 0 eth0
[root@jfht ~]# /sbin/route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
211.103.28.0 0.0.0.0 255.255.255.224 U 0 0 0 eth0
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1
169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth1
0.0.0.0 211.103.28.1 0.0.0.0 UG 0 0 0 eth0
[root@jfht ~]#

示例二 打印当前路由表(非root用户)
[web@hnweb1 ~]$ route
-bash: route: command not found
[web@hnweb1 ~]$ /sbin/route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
10.66.10.0 * 255.255.255.128 U 0 0 0 eth0
192.130.12.0 10.66.10.1 255.255.255.0 UG 0 0 0 eth0
10.0.0.0 * 255.255.255.0 U 0 0 0 eth1
10.66.0.0 10.66.10.1 255.255.0.0 UG 0 0 0 eth0
134.161.0.0 10.66.10.1 255.255.0.0 UG 0 0 0 eth0
10.20.0.0 10.66.10.1 255.255.0.0 UG 0 0 0 eth0
169.254.0.0 * 255.255.0.0 U 0 0 0 eth1
172.224.0.0 10.66.10.1 255.255.0.0 UG 0 0 0 eth0
default 10.66.10.22 0.0.0.0 UG 0 0 0 eth0
[web@hnweb1 ~]$ route -n
-bash: route: command not found
[web@hnweb1 ~]$ /sbin/route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
10.66.10.0 0.0.0.0 255.255.255.128 U 0 0 0 eth0
192.130.12.0 10.66.10.1 255.255.255.0 UG 0 0 0 eth0
10.0.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1
10.66.0.0 10.66.10.1 255.255.0.0 UG 0 0 0 eth0
134.161.0.0 10.66.10.1 255.255.0.0 UG 0 0 0 eth0
10.20.0.0 10.66.10.1 255.255.0.0 UG 0 0 0 eth0
169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth1
172.224.0.0 10.66.10.1 255.255.0.0 UG 0 0 0 eth0
0.0.0.0 10.66.10.22 0.0.0.0 UG 0 0 0 eth0
[web@hnweb1 ~]$

示例三 设置到某网络的路由的例子
下面的例子 来自一个实际的服务器配置。 route命令写在了/etc/rc.local中,这样就设置了一条永久路由。

[root@jf07 root]# grep route /etc/rc.local
route add -net 10.0.0.0/8 gw 10.33.149.1 dev eth1
[root@jf07 root]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
10.32.181.182 10.33.149.1 255.255.255.255 UGH 0 0 0 eth1
10.33.136.135 10.33.149.1 255.255.255.255 UGH 0 0 0 eth1
10.32.208.13 10.33.149.1 255.255.255.255 UGH 0 0 0 eth1
10.33.149.0 * 255.255.255.128 U 0 0 0 eth1
192.168.1.0 * 255.255.255.0 U 0 0 0 eth0
169.254.0.0 * 255.255.0.0 U 0 0 0 eth1
10.0.0.0 10.33.149.1 255.0.0.0 UG 0 0 0 eth1
default 192.168.1.254 0.0.0.0 UG 0 0 0 eth0
[root@jf07 root]#

示例四 添加拒绝路由的测试
[root@jfht ~]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
211.103.28.0 * 255.255.255.224 U 0 0 0 eth0
192.168.1.0 * 255.255.255.0 U 0 0 0 eth1
169.254.0.0 * 255.255.0.0 U 0 0 0 eth1
default 211.103.28.1 0.0.0.0 UG 0 0 0 eth0
[root@jfht ~]# ping 10.33.11.12
PING 10.33.11.12 (10.33.11.12) 56(84) bytes of data.
Ctrl+C
— 10.33.11.12 ping statistics —
21 packets transmitted, 0 received, 100% packet loss, time 19999ms

[root@jfht ~]# route add -net 10.0.0.0 netmask 255.0.0.0 reject
[root@jfht ~]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
211.103.28.0 * 255.255.255.224 U 0 0 0 eth0
192.168.1.0 * 255.255.255.0 U 0 0 0 eth1
169.254.0.0 * 255.255.0.0 U 0 0 0 eth1
10.0.0.0 – 255.0.0.0 ! 0 – 0 –
default 211.103.28.1 0.0.0.0 UG 0 0 0 eth0
[root@jfht ~]# ping 10.33.11.12
connect: Network is unreachable
[root@jfht ~]#

示例五 设置路由之后重启机器的测试
[root@node34 root]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.227.0 * 255.255.255.0 U 0 0 0 eth0
169.254.0.0 * 255.255.0.0 U 0 0 0 eth0
default 192.168.227.2 0.0.0.0 UG 0 0 0 eth0
[root@node34 root]# route add -net 10.0.0.0 netmask 255.0.0.0 reject
[root@node34 root]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.227.0 * 255.255.255.0 U 0 0 0 eth0
169.254.0.0 * 255.255.0.0 U 0 0 0 eth0
10.0.0.0 – 255.0.0.0 ! 0 – 0 –
default 192.168.227.2 0.0.0.0 UG 0 0 0 eth0
[root@node34 root]# reboot

Broadcast message from root (pts/0) (Thu Jul 7 05:31:26 2011):

The system is going down for reboot NOW!
[root@node34 root]#

Last login: Thu Jul 7 05:30:50 2011 from 192.168.227.1
[root@node34 root]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.227.0 * 255.255.255.0 U 0 0 0 eth0
169.254.0.0 * 255.255.0.0 U 0 0 0 eth0
default 192.168.227.2 0.0.0.0 UG 0 0 0 eth0
[root@node34 root]#

上面的测试表明route设置的路由在机器重启之后就消失了。

示例六 将route命令添加到/etc/rc.local来设置永久路由的测试
先用vi在/etc/rc.local后面添加route命令。

[root@node34 root]# tail /etc/rc.local
#
# This script will be executed *after* all the other init scripts.
# You can put your own initialization stuff in here if you don’t
# want to do the full Sys V style init stuff.

touch /var/lock/subsys/local

# 2011.07.15 add permanent route test
route add -net 10.0.0.0 netmask 255.0.0.0 reject

[root@node34 root]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.227.0 * 255.255.255.0 U 0 0 0 eth0
169.254.0.0 * 255.255.0.0 U 0 0 0 eth0
default 192.168.227.2 0.0.0.0 UG 0 0 0 eth0
[root@node34 root]# reboot

Broadcast message from root (pts/0) (Fri Jul 15 14:43:44 2011):

The system is going down for reboot NOW!
[root@node34 root]#

Last login: Fri Jul 15 14:40:22 2011 from 192.168.227.1
[root@node34 root]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.227.0 * 255.255.255.0 U 0 0 0 eth0
169.254.0.0 * 255.255.0.0 U 0 0 0 eth0
10.0.0.0 – 255.0.0.0 ! 0 – 0 –
default 192.168.227.2 0.0.0.0 UG 0 0 0 eth0
[root@node34 root]#

示例七 删除路由的测试
删除路由的时候只需将route add改成route del,其他参数类似。如果报“无效的参数”或“没有那个进程”,可能是因为提供的参数不够。

[root@node34 root]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.227.0 * 255.255.255.0 U 0 0 0 eth0
169.254.0.0 * 255.255.0.0 U 0 0 0 eth0
10.0.0.0 – 255.0.0.0 ! 0 – 0 –
default 192.168.227.2 0.0.0.0 UG 0 0 0 eth0
[root@node34 root]#
[root@node34 root]# route del -net 10.0.0.0
SIOCDELRT: 无效的参数
[root@node34 root]# route del -net 10.0.0.0 netmask 255.0.0.0
SIOCDELRT: 没有那个进程
[root@node34 root]#
[root@node34 root]# route del -net 10.0.0.0 netmask 255.0.0.0 reject
[root@node34 root]#
[root@node34 root]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.227.0 * 255.255.255.0 U 0 0 0 eth0
169.254.0.0 * 255.255.0.0 U 0 0 0 eth0
default 192.168.227.2 0.0.0.0 UG 0 0 0 eth0
[root@node34 root]#

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