虛擬化技術基礎原理
阿新 • • 發佈：2018-11-11
程式侷限性原因：
空間侷限性
時間侷限性
IO裝置的部分：
裝置控制器和裝置本身
控制器：整合在主機板上的一塊晶片或一組晶片
驅動程式：通常應該由裝置生產商：位於核心中
每個控制器都有少量的用於通訊的暫存器，每個暫存器表現為一個I/O埠；
所有的暫存器組合成為裝置的IO地址空間；
實現輸入、輸出： 三種方式： 1、輪詢：忙等待 2、中斷： 核心處理中斷分為兩步： 中斷上半部、中斷的下半部 3、DMA： OS： cpu：時間片，time slice memory：虛擬地址空間 I/O：檔案 程序 資源集 cpu事件 memory：抽象，虛擬地址空間（32bits：4G） I/O：開啟的多個檔案，fd（file descriptor） 正常檔案 裝置檔案 管道檔案 程序：task cpu虛擬化： 模擬：emulation 虛擬：virtulization 完全虛擬化（full-virtulization） BT：二進位制翻譯（軟體） HVM：硬體輔助的虛擬化（硬體） 半虛擬化： Memory： 程序：現行地址空間 核心：實體地址空間 MMU Virtulization Inter：EPT，Extended Page Table AMD：NTP，Nested Page Table TLB virtulization tagged TLB I/O： 外存： 硬碟、光碟、U盤 網路裝置： 網絡卡 顯示裝置： VGA：frame buffer機制 鍵盤滑鼠： ps/2，usb I/O虛擬化的方式： 模擬：完全使用軟體來模擬真實硬體 半虛擬化： IO-through：IO透傳 Inter：VT-d 基於北橋的硬體輔助的虛擬化技術： 兩種實現方式： Type-I： xen，vmware ESX/ESXi Type-II： kvm，vmware，workstation，virtualbox
Inter硬體輔助的虛擬化：
CPU：vt-x，EPT，tagged-TLB
IO/CPU：vt-d，IOV，VMDq
第一類：跟處理器相關：vt-x
第二類：跟晶片相關：vt-d
第三類：跟IO相關：VMDq和SR-IOVQEMU，virtio
虛擬化技術的分類
模擬：著名的模擬器，PearPC，Bochs，QEMU
完全虛擬化：也稱為native virtulization
兩種加速方式：
BT
HVM
VMware Workstation，VMware Server，Parallels Desktop，KVM，Xen（HVM）
半虛擬化：para-virtualization xen，uml（user-mod linux） OS級別的虛擬化： OpenVZ，lxc Solaris Contaniners FreeBSD jails 庫虛擬化： wine， 應用程式虛擬化： jvm
虛擬化網路：
nat mode
bridge mode
routed mode
isolation mode
使用brctl的配置過程：
# brctl add br0
# brctl stp br0 on
# ifconfig eth0 0 up
# brctl addif br0 eth0
# ifconfig br0 IP/NETMASK up
# route add default gw GW TUN與TAP
在計算機網路中，TUN與TAP是作業系統核心中的虛擬網路裝置，不同於普通靠硬體網路辦卡實現的裝置，這些虛擬的網路裝置全部用軟體實現，並向運行於作業系統上的軟體提供與硬體的網路裝置完全相同的功能；
TAP等同於一個乙太網裝置，它操作第二層資料包如乙太網資料幀，TUN模擬了網路層裝置，操作第三層資料包如IP資料包。
作業系統通過TUN/TAP裝置向繫結該裝置的使用者空間的程式傳送資料，反之，使用者空間的程式也可以像操作硬體的網路裝置那樣，通過TUN/TAP裝置傳送資料，在後種情況下，TUN/TAP裝置向作業系統的網路棧投遞（或"注入"）資料包，從而模擬從外部接受資料的過程。
[[email protected] ~]# ifconfig
eth0 Link encap:Ethernet HWaddr 00:0C:29:11:21:56
inet addr:192.168.10.6 Bcast:192.168.10.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fe11:2156/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:141 errors:0 dropped:0 overruns:0 frame:0
TX packets:74 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:14934 (14.5 KiB) TX bytes:9717 (9.4 KiB)
eth1 Link encap:Ethernet HWaddr 00:0C:29:11:21:60
inet addr:192.168.190.128 Bcast:192.168.190.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fe11:2160/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:193 errors:0 dropped:0 overruns:0 frame:0
TX packets:30 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:16345 (15.9 KiB) TX bytes:3153 (3.0 KiB)
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)橋不支援NetworkManger管理，需要關閉NetworkManger啟動[[email protected] ~]# chkconfig --list NetworkManager
橋使用network管理
[[email protected] ~]# chkconfig --list network
network 0:關閉 1:關閉 2:啟用 3:啟用 4:啟用 5:啟用 6:關閉[root[email protected] ~]# yum -y install bridge-utils
[[email protected] ~]# rpm -ql bridge-utils
/usr/sbin/brctl
/usr/share/doc/bridge-utils-1.2
/usr/share/doc/bridge-utils-1.2/AUTHORS
/usr/share/doc/bridge-utils-1.2/COPYING
/usr/share/doc/bridge-utils-1.2/FAQ
/usr/share/doc/bridge-utils-1.2/HOWTO
/usr/share/man/man8/brctl.8.gz[[email protected] ~]# cd /etc/sysconfig/network-scripts/
[[email protected] network-scripts]# cp ifcfg-eth0 ifcfg-br0關閉NetworkManger服務進行管理：NM_CONTROLLED=no
[[email protected] network-scripts]# vim ifcfg-br0
DEVICE=br0
TYPE=Bridge
ONBOOT=yes
NM_CONTROLLED=no
BOOTPROTO=none
IPADDR=192.168.10.6
NETMASK=255.255.255.0[[email protected] network-scripts]# vim ifcfg-eth0
DEVICE=eth0
HWADDR=00:0C:29:11:21:56
TYPE=Ethernet
UUID=f343369c-4aa9-4975-81b3-3f38f4c56ef0
ONBOOT=yes
NM_CONTROLLED=no
BOOTPROTO=none
BRIDGE=br0[[email protected] network-scripts]# service network restart
正在關閉介面 eth0： bridge br0 does not exist!
[確定]
正在關閉介面 eth1： [確定]
關閉環回介面： [確定]
彈出環回介面： [確定]
彈出介面 eth0： [確定]
彈出介面 eth1：
正在決定 eth1 的 IP 資訊...完成。
[確定]
彈出介面 br0： Determining if ip address 192.168.10.6 is already in use for device br0...
[確定][[email protected] network-scripts]# ifconfig
br0 Link encap:Ethernet HWaddr 00:0C:29:11:21:56
inet addr:192.168.10.6 Bcast:192.168.10.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fe11:2156/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:21 errors:0 dropped:0 overruns:0 frame:0
TX packets:20 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:2174 (2.1 KiB) TX bytes:2264 (2.2 KiB)
eth0 Link encap:Ethernet HWaddr 00:0C:29:11:21:56
inet6 addr: fe80::20c:29ff:fe11:2156/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:1353 errors:0 dropped:0 overruns:0 frame:0
TX packets:1217 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:105072 (102.6 KiB) TX bytes:120035 (117.2 KiB)
eth1 Link encap:Ethernet HWaddr 00:0C:29:11:21:60
inet addr:192.168.190.128 Bcast:192.168.190.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fe11:2160/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:19201 errors:0 dropped:0 overruns:0 frame:0
TX packets:8181 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:27802761 (26.5 MiB) TX bytes:449250 (438.7 KiB)
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)[[email protected] network-scripts]# brctl show
bridge name bridge id STP enabled interfaces
br0 8000.000c29112156 no eth0[[email protected] network-scripts]# brctl --help
Usage: brctl [commands]
commands:
addbr <bridge> add bridge
delbr <bridge> delete bridge
addif <bridge> <device> add interface to bridge
delif <bridge> <device> delete interface from bridge
setageing <bridge> <time> set ageing time
setbridgeprio <bridge> <prio> set bridge priority
setfd <bridge> <time> set bridge forward delay
sethello <bridge> <time> set hello time
setmaxage <bridge> <time> set max message age
sethashel <bridge> <int> set hash elasticity
sethashmax <bridge> <int> set hash max
setmclmc <bridge> <int> set multicast last member count
setmcrouter <bridge> <int> set multicast router
setmcsnoop <bridge> <int> set multicast snooping
setmcsqc <bridge> <int> set multicast startup query count
setmclmi <bridge> <time> set multicast last member interval
setmcmi <bridge> <time> set multicast membership interval
setmcqpi <bridge> <time> set multicast querier interval
setmcqi <bridge> <time> set multicast query interval
setmcqri <bridge> <time> set multicast query response interval
setmcqri <bridge> <time> set multicast startup query interval
setpathcost <bridge> <port> <cost> set path cost
setportprio <bridge> <port> <prio> set port priority
setportmcrouter <bridge> <port> <int> set port multicast router
show [ <bridge> ] show a list of bridges
showmacs <bridge> show a list of mac addrs
showstp <bridge> show bridge stp info
stp <bridge> {on|off} turn stp on/off[[email protected] network-scripts]# brctl stp br0 on
[[email protected] network-scripts]# brctl show
bridge name bridge id STP enabled interfaces
br0 8000.000c29112156 yes eth0命令建立橋：
[[email protected] ~]# ifconfig
eth0 Link encap:Ethernet HWaddr 00:0C:29:E8:20:12
inet addr:192.168.10.7 Bcast:192.168.10.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fee8:2012/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:27 errors:0 dropped:0 overruns:0 frame:0
TX packets:40 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:4781 (4.6 KiB) TX bytes:5365 (5.2 KiB)
eth1 Link encap:Ethernet HWaddr 00:0C:29:E8:20:1C
inet addr:192.168.190.129 Bcast:192.168.190.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fee8:201c/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:40 errors:0 dropped:0 overruns:0 frame:0
TX packets:15 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:3072 (3.0 KiB) TX bytes:1511 (1.4 KiB)
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)[[email protected] ~]# chkconfig --list NetworkManager
[[email protected] ~]# chkconfig --list network
network 0:關閉 1:關閉 2:啟用 3:啟用 4:啟用 5:啟用 6:關閉
[[email protected] ~]# yum -y install bridge-utils[[email protected] ~]# brctl --help
Usage: brctl [commands]
commands:
addbr <bridge> add bridge
delbr <bridge> delete bridge
addif <bridge> <device> add interface to bridge
delif <bridge> <device> delete interface from bridge
setageing <bridge> <time> set ageing time
setbridgeprio <bridge> <prio> set bridge priority
setfd <bridge> <time> set bridge forward delay
sethello <bridge> <time> set hello time
setmaxage <bridge> <time> set max message age
sethashel <bridge> <int> set hash elasticity
sethashmax <bridge> <int> set hash max
setmclmc <bridge> <int> set multicast last member count
setmcrouter <bridge> <int> set multicast router
setmcsnoop <bridge> <int> set multicast snooping
setmcsqc <bridge> <int> set multicast startup query count
setmclmi <bridge> <time> set multicast last member interval
setmcmi <bridge> <time> set multicast membership interval
setmcqpi <bridge> <time> set multicast querier interval
setmcqi <bridge> <time> set multicast query interval
setmcqri <bridge> <time> set multicast query response interval
setmcqri <bridge> <time> set multicast startup query interval
setpathcost <bridge> <port> <cost> set path cost
setportprio <bridge> <port> <prio> set port priority
setportmcrouter <bridge> <port> <int> set port multicast router
show [ <bridge> ] show a list of bridges
showmacs <bridge> show a list of mac addrs
showstp <bridge> show bridge stp info
stp <bridge> {on|off} turn stp on/off[[email protected] ~]# brctl show
bridge name bridge id STP enabled interfaces
[[email protected] ~]# brctl addbr br0[[email protected] ~]# ifconfig
eth0 Link encap:Ethernet HWaddr 00:0C:29:E8:20:12
inet addr:192.168.10.7 Bcast:192.168.10.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fee8:2012/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:557 errors:0 dropped:0 overruns:0 frame:0
TX packets:385 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:48970 (47.8 KiB) TX bytes:39748 (38.8 KiB)
eth1 Link encap:Ethernet HWaddr 00:0C:29:E8:20:1C
inet addr:192.168.190.129 Bcast:192.168.190.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fee8:201c/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:5053 errors:0 dropped:0 overruns:0 frame:0
TX packets:2694 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:7236029 (6.9 MiB) TX bytes:148485 (145.0 KiB)
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:2 errors:0 dropped:0 overruns:0 frame:0
TX packets:2 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:200 (200.0 b) TX bytes:200 (200.0 b)[[email protected] ~]# ifconfig eth0 0 up
[[email protected] ~]# ifconfig
eth0 Link encap:Ethernet HWaddr 00:0C:29:E8:20:12
inet6 addr: fe80::20c:29ff:fee8:2012/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:600 errors:0 dropped:0 overruns:0 frame:0
TX packets:404 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:52372 (51.1 KiB) TX bytes:41802 (40.8 KiB)
eth1 Link encap:Ethernet HWaddr 00:0C:29:E8:20:1C
inet addr:192.168.190.129 Bcast:192.168.190.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fee8:201c/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:5118 errors:0 dropped:0 overruns:0 frame:0
TX packets:2749 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:7247051 (6.9 MiB) TX bytes:156881 (153.2 KiB)
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:2 errors:0 dropped:0 overruns:0 frame:0
TX packets:2 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:200 (200.0 b) TX bytes:200 (200.0 b)[[email protected] ~]# brctl addif br0 eth0
[[email protected] ~]# ifconfig br0 192.168.10.7/24 up
[[email protected] ~]# route add default gw 192.168.10.254[[email protected] ~]# ifconfig
br0 Link encap:Ethernet HWaddr 00:0C:29:E8:20:12
inet addr:192.168.10.7 Bcast:192.168.10.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fee8:2012/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:24 errors:0 dropped:0 overruns:0 frame:0
TX packets:6 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:1104 (1.0 KiB) TX bytes:468 (468.0 b)
eth0 Link encap:Ethernet HWaddr 00:0C:29:E8:20:12
inet6 addr: fe80::20c:29ff:fee8:2012/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:632 errors:0 dropped:0 overruns:0 frame:0
TX packets:410 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:54292 (53.0 KiB) TX bytes:42270 (41.2 KiB)
eth1 Link encap:Ethernet HWaddr 00:0C:29:E8:20:1C
inet addr:192.168.190.129 Bcast:192.168.190.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fee8:201c/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:5331 errors:0 dropped:0 overruns:0 frame:0
TX packets:2881 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:7263087 (6.9 MiB) TX bytes:168737 (164.7 KiB)
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:2 errors:0 dropped:0 overruns:0 frame:0
TX packets:2 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:200 (200.0 b) TX bytes:200 (200.0 b)