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$ sudo route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.100.0 * 255.255.255.0 U 0 0 0 eth1
192.168.10.0 * 255.255.254.0 U 0 0 0 eth0
default 192.168.10.1 0.0.0.0 UG 0 0 0 eth0
--------------------------------------------------------------------------------------
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The output of the kernel routing table is organized in the following columns
Destination
The destination network or destination host.
Gateway
The gateway address or '*' if none set.
Genmask
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
U (route is up)
H (target is a host)
G (use gateway)
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 The 'distance' to the target (usually counted in hops). It is not used by recent kernels, but may be needed by
routing daemons.
Ref Number of references to this route. (Not used in the Linux kernel.)
Use 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 Interface to which packets for this route will be sent.
MSS Default maximum segment size for TCP connections over this route.
Window Default window size for TCP connections over this route.
irtt Initial RTT (Round Trip Time). The kernel uses this to guess about the best TCP protocol parameters without wait-
ing on (possibly slow) answers.
HH (cached only)
The number of ARP entries and cached routes that refer to the hardware header cache for the cached route. This
will be -1 if a hardware address is not needed for the interface of the cached route (e.g. lo).
Arp (cached only)
Whether or not the hardware address for the cached route is up to date
ããåæ¶å¨freebsdä¸ä½¿ç¨netstat -nræå°è·¯ç±è¡¨ï¼ä¹é¡ºä¾¿æ示ä¸ä¸ã
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man routeæ¥çæ¹æ³ï¼æ许å个系ç»ç¥æå·®å¼ï¼ä¸é¢æ¯ä»¥debian为ä¾ï¼ç±äºæ¯æµè¯ï¼æ以使ç¨sudoï¼èä¸æ¯rootæéï¼
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$ sudo route add âhost 192.168.10.58 dev eth1
//ææéå192.168.10.58çæ°æ®é½æ¯ç¨eth1ç½å¡
$ sudo route add âhost 192.168.11.58 gw 192.168.10.1
//éå192.168.11.58çæ°æ®ä½¿ç¨ç½å
³192.168.10.1
ããä¸ç»æé´åäºä¸ä¸ªéªè¯å®éªï¼ç±äºeth1æ¯æ²¡æå¯å¨çï¼æ以添å è¿ä¸ªè·¯ç±åï¼192.168.10.58ä¸å¯pingé
åå§è·¯ç±è¡¨
sudo route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.100.0 * 255.255.255.0 U 0 0 0 eth1
192.168.10.0 * 255.255.254.0 U 0 0 0 eth0
default 192.168.10.1 0.0.0.0 UG 0 0 0 eth0
----------------------------------------------------------------------------
ããå¯ä»¥pingé192.168.10.58
$ ping 192.168.10.58
PING 192.168.10.58 (192.168.10.58) 56(84) bytes of data.
64 bytes from 192.168.10.58: icmp_seq=1 ttl=64 time=0.188 ms
-----------------------------------------------------------------------------
ããæ·»å 192.168.10.58çè·¯ç±
$ sudo route add -host 192.168.10.58 dev eth1
$ sudo route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.10.58 * 255.255.255.255 UH 0 0 0 eth1
192.168.100.0 * 255.255.255.0 U 0 0 0 eth1
192.168.10.0 * 255.255.254.0 U 0 0 0 eth0
default 192.168.10.1 0.0.0.0 UG 0 0 0 eth0
----------------------------------------------------------------------------
ããç±äºeth0æ æ³ä½¿ç¨äºï¼æ以åç»eth1ï¼å°±çäºä¸¢å
¥é»æ´ä¹ä¸
$ ping 192.168.10.58
PING 192.168.10.58 (192.168.10.58) 56(84) bytes of data.
--- 192.168.10.58 ping statistics ---
2 packets transmitted, 0 received, 100% packet loss, time 1010ms
----------------------------------------------------------------------------
ããæå®ç»ç½å
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$ sudo route add -host 192.168.10.58 gw 192.168.10.1
$ sudo route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.10.58 192.168.10.1 255.255.255.255 UGH 0 0 0 eth0
192.168.10.58 * 255.255.255.255 UH 0 0 0 eth1
192.168.100.0 * 255.255.255.0 U 0 0 0 eth1
192.168.10.0 * 255.255.254.0 U 0 0 0 eth0
default 192.168.10.1 0.0.0.0 UG 0 0 0 eth0
----------------------------------------------------------------------------
ããè¦ç»è¿ç½å
³äºï¼éªè¯äºè·¯ç±è¡¨çä½ç¨
$ ping 192.168.10.58
PING 192.168.10.58 (192.168.10.58) 56(84) bytes of data.
From 192.168.10.1: icmp_seq=1 Redirect Network(New nexthop: 192.168.10.58)
64 bytes from 192.168.10.58: icmp_seq=1 ttl=64 time=1.02 ms
----------------------------------------------------------------------------
ããåºè¯å°è¯´äºï¼åç为æç½è·¯æ·»å è·¯ç±åå é¤è·¯ç±å¦ä¸æ示ï¼ç»è¿æµè¯ææï¼
ãã2ã为æç½ç»çæ·»å è·¯ç±
$ sudo route add ânet 220.181.8.0/24 dev eth0
$ sudo route add ânet 220.181.8.0/24 gw 192.168.10.1
ãã3ãæ·»å é»è®¤ç½å
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$ sudo route add default gw 192.168.10.1
4ãå é¤è·¯ç±ï¼
$ sudo route del âhost 192.168.168.110 dev eth0
ããå¯è½ä½ ä¼éå°å é¤æ¶åè¯æ³é误ï¼è¯·åçè·¯ç±è¡¨çFlags,è·¯ç±ä¸é¢ç第ä¸æ¡ï¼G表示设å®äºç½å
³ï¼H表示æä½äºä¸»æºï¼æ以就ç¨$ sudo route del -host 192.168.10.58 gw 192.168.10.1å é¤ï¼æ´è¯¦ç»ç请manã
ãã使ç¨route å½ä»¤æ·»å çè·¯ç±ï¼æºå¨éå¯æè
ç½å¡éå¯åè·¯ç±å°±å¤±æäºï¼åiptablesä¸æ ·ï¼éè¦æ°¸ä¹
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ãã1.å¨/etc/rc.localéæ·»å æ§è¡å½ä»¤ï¼è¿è¡å¼æºæ§è¡ï¼å 为æ¯rootæéï¼æ以ä¸ç¨sudoäºï¼
route add ânet 220.181.8.0/24 dev eth0
route add ânet 220.181.9.0/24 gw 192.168.10.1
ãã2.å¨/etc/sysconfig/networkéæ·»å å°æ«å°¾
æ¹æ³ï¼GATEWAY=gw-ip æè
GATEWAY=gw-dev
ãã3./etc/sysconfig/static-router :
any net x.x.x.x/24 gw y.y.y.y
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