Windows NT server is used as a router
Windows NT server is used as router 2000-05-26 · Unknown CPCW network technology to today, no longer limit in a small LAN. In the daily network, the most encountered is to connect the existing network, achieve maximum resource sharing, information interoperability. Putting different networks, what kind of protocol is adopted. TCP / IP has developed so far and has become a widely used network general protocol. Approved by the majority of computer users. With TCP / IP, you can easily connect internets between networks of different networks, and different operating systems, while it can be easily coupled to the Internet. In TCP / IP network interconnection, interconnection of different networks often use the router. Traditional hardware-based router prices are often higher, not for general units, and during the networking process, the problems that often encounter will interconnect two or two local area networks, and they do not use expensive. Dedicated router. In fact, there are many network operating systems that provide routing functions, just software-based routing, such as Windows NT static routing system, Novell's multi-protocol routing MPR, etc. Based on software-based routing technology. Software-based routing, function is definitely better than hardware-based dedicated routers. But it already has the basic functions of the router. Basic routing functions can be implemented. Software-based routing is ideal for small networks. Software-based routing techniques are described below with internet interconnection. As we all know, in the TCP / IP protocol, IP protocol (Internet Protocol) provides addressing and routing. When data is sent on the network, the data is first packaged and becomes an IP packet. IP allows packets to pass from one place from one place to another. The transmission of data in the network is performed in one way. In an Ethernet, it is easy to send the message from a machine to another. Because Ethernet is a broadcast-based network, and the packets issued on any machine will be immediately connected to all machines. Surpantly, only the machine that is only the same as the address in the message will be responded, and the other machines will ignore this information. It can be seen that inside the same network, each message does not have to select the path, you can directly reach its destination. However, when two or more network interconnections, the situation is bigger. As shown in Figure 1, when a machine in the network counter wants to send information to a machine in the network computer center, if there is no route from the network counter to the network Computer Center, the information is not available at all. Arrived. From the above analysis: Since information in the same network can be smoothly transmitted, then if there is such a machine: a machine that belongs to the network counter and the network Computer Center. With it, two different networks can pass information. In fact, in Windows NT, IP route is the function of IP. NT allows a machine to be formulated into a multi-hook. That is, on the same computer, two or more network cards are installed, and each block is connected to a network. From this machine as a router, the route of the IP package is performed between the two networks. This route is a static route, and the static router requires manual construction and updating the routing table. In the case of each network has been built, establish a NT router, its establishment procedure is as follows: 1. Install two network cards in the same Windows NT machine, and the NIC can use the NT support. Windows NT can be Windows NT Server or Windows NT Workstation, the version is preferably 3.51 or higher.
Based on WIN? DowsNTServer4.0 Chinese version. 2, enter the control panel, install the TCP / IP protocol 3, configure a network card: Configure an IP address for each block, and the two IP addresses belong to the IP address within a different network. 4. Set the IP routing function of Windows NT for enable. 5. After confirmation, restart the computer. In this way, the NT router can work in both networks. The NT router work process is as follows: A computer counter01 in the Counter network is to send information to a computer CC01 in the Computer Center network. It queries whether the CC01 is in the same network through the broadcast mode. If it is in the same network, the packet is transmitted by the COUNTER1 to the CC01, and the IP package is transmitted in the same network. If you pass the query, I found that the CC01 is not in the same network, and I will issue some counter1 to find that I don't know how to reach the CC01 at all. In this case, the packet is sent to the default gateway: Router1 (When in the network, you must pass online counter in advance The default router of each machine is set to Router1. The IP address is the IP address of Router1. For each machine within the network, the default router is actually such a machine, if you send a message point not When it comes to the destination address, it sends the information to the default router. After the router is sent to it), after the Router1 receives the information, the information is checked by the IP software running on it, and can be determined by checking the package content. The source address and destination address in the IP package, if the source IP address in the IP package is found to be in the same network with the IP address of the first network card, the target IP address is in the same network with the second block, it will This information is sent to the network computer center through its second network card. Once the packet enters the network computer center, the destination computer listening to the network is sent to yourself, so it receives the packet and recombines them. The above is the case where the NT router works within two networks. It is indeed a great task, but if there are three or more networks, the methods mentioned above cannot be eligible. Please see the following network structure: Router1 router can only pass the message 192.168.101 to the network 168.168, but cannot pass the information from the network 192.168.101 to network admin (195.125.96). However, the route command in NT can tell the router how to reach AdminCenter. For Router1 and Router2, they all belong to the network of Computer Center at the same time, so the router can be issued to the AdminCenter through the ComputerCenter network (193.169.101). Network (195.125.96), just tell the Router2 network card address in the Network Computer Center.
The command format is as follows: c: ιWinntλrouteadd195.125.96168.168.100.100 This command will add routing information to the routing table of Router1, which is intended to put any objects 195.125.96. XXX's IP package is sent to 168.168.100.100. Similarly, for network adminCenter, router Router2 does not know how to reach the Counter network (192.168.101), but also tell it how to arrive. The command format is as follows: c: ιWinntλrouteadd192.168.101168.168.100.101 functionally. In fact, we can implement the above functions by establishing a static routing table, establish a static routing table on Router1, Router2, and the static routing table requires a goal and a gateway. The target is the network ID or network name of the target network, the gateway is The IP address or host name connected to the target network. The content is as follows: For Router1, the routing table is constructed with the network ID of the network application and its default gateway. The gateway is an IP address or host name of a computer connected to the target network. The static routing table is as follows: Target Network Gateway 195.125.96168.168.100.100 Admin Runr2 For Router2, you need to construct a routing table with the network ID of the Network Counter and its default gateway. The gateway is an IP address or host name of a computer connected to the target network. The static routing table is as follows: Target Network Gateway 192.168.101168.168.100.101 Counterrouter1 The corresponding NetWorks file content is as follows: # wDOWSNT4.0NetworksContent Counter192.168.101 admin195.125.96 loopback127 ............. computer168. 168 The corresponding HOSTS file is as follows: 192.168.101.1counter1counter1. Saturn. COM 168.168.100.1cc01cc01. Saturn. com .......... # ... to this, the three networks can be passed through the route information. Some people say that you can also configure a router with the adminCenter between Counter. Indeed, if a router Router3 is configured between Counter, the machine in each network, the path between each computer is passed, which makes a path to a path due to crowding or accidental failure. When not smooth, they can still communicate as usual. This requires that each computer in the network is configured to use a plurality of gateways. Router NAT Features Configuration Profile (Knowledge Point Explain, BSCI
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With the rapid development of Internet's network, the shortage of IP addresses has become a very prominent issue. In order to solve this problem, there have been a variety of solutions. The following sessile is a more effective method, an address conversion (NAT) function, which is more effective in the current network environment. First, NAT introduction
The function of NAT (Network Address Translation) is to refer to an IP address within a network, which can be free from the IP address, without the need to apply. Inside the network, each computer communicates with the internal IP address. When the internal computer is to communicate with an external Internet network, a device with a NAT function (such as a router) is responsible for communicating the IP address therebetween to legitimate IP addresses (ie, the application IP address) communicates.
Second, NAT application environment:
Situation 1: An enterprise does not want external network users to know their own network internal structures, can isolate the internal network with external Internet by NAT, and external users do not know the internal IP address set by NAT.
Case 2: The legal Internet IP address of a business application is small, and there are many internal network users. A plurality of users can be implemented by NAT functions simultaneously a legal IP is communicating with external Internet.
Third, set the hardware configuration and software configuration of the router required for NAT:
The router that sets the NAT function must have at least one internal port (Inside), an external port (Outside). The network user connected to the internal port is used by an internal IP address.
The internal port can be any router port. External ports are connected to external networks, such as Internet. The external port can be any port on the router.
The IOS of the router that sets the NAT function should support the NAT function (the router used in this article is Cisco2501, which supports the NAT function above 11.2.).
Fourth, there are several concepts about NAT:
Inside local address: Assigned to the internal IP address of the computer in the internal network.
Inside Global Address: When entering IP communication, represents one or more of the legitimate IP addresses of one or more internal local addresses. The IP address that needs to be applied.
V. NAT setting method:
NAT settings can be divided into static address translation, dynamic address translation, multiplex dynamic address translation.
1, static address translation applicable environment
Static address conversion will convert the internal local address with the internal legitimate address and need to specify and which legal address is converted. If the internal network has an E-mail server or the FTP server, the IP address of these servers must be converted to external users so that external users can use them.
Static address conversion basic configuration steps:
(1) Establish a static address conversion between the internal local address and the internal legal address. Enter: in the global settings:
IP Nat Inside Source Static internal local address internal legal address
(2), specify the internal port of the connection network in the port settings:
IP Nat INSIDE
(3), specifying the external port of the connection external network in port settings:
IP Nat Outside
Note: The plurality of internal ports and multiple external ports can be defined according to actual needs.
Example 1:
This example implements a static NAT address conversion function. The ETH port of 2501 is used as the internal port, and the synchronous port 0 is used as the external port. The internal local addresses of 10.1.1.2, 10.1.1.3, 10.1.1.4 use static address translation. Its internal legal address corresponds to 192.1.1.2, 192.1.1.3, 192.1.1.4, respectively. The configuration of the router 2501:
CURRENT Configuration:
Version 11.3
No Service Password-Encryption
Hostname 2501
IP Nat Inside Source Static 10.1.1.2 192.1.1.2
IP Nat Inside Source Static 10.1.1.3 192.1.1.3
IP Nat Inside Source Static 10.1.1.4 192.1.1.4
Interface Ethernet0
IP Address 10.1.1.1 255.255.255.0
IP Nat INSIDE
Interface serial0
IP Address 192.1.1.1 255.255.255.0
IP Nat Outside
NO ip mroute-cache
Bandwidth 2000
NO FAIR-Queue
ClockRate 2000000
Interface serial1
No ip address
Shutdown
NO ip classless
IP Route 0.0.0.0 0.0.0.0 Serial0
Line Con 0
LINE AUX 0
Line Vty 0 4
Password Cisco
end
You can use the following statement after the configuration is complete:
SHOW IP Nat Statistcs
Show ip nat translations
2, dynamic address translation applicable environment:
Dynamic address conversion also converts the local address with the internal legal address one-to-one, but dynamic address translation is dynamically selected from the internal legal address pool to convert the internal local address.
Dynamic address conversion Basic configuration steps:
(1) In the global setting mode, the internal legal address pool is defined.
IP Nat Pool Address Pool Name Start IP Address Termination IP Address Subnet Mask
Where address pool names can be set.
(2) In the global setting mode, define a standard Access-List rule to allow which internal addresses can perform dynamic address translation.
Access-List Number Permit Source Address Corner
The integer between 1-99 is 1-99.
(3) In the global setting mode, the internal local address specified by Access-List is interested in addressing the address pool of the specified internal legitimate address pool.
IP NAT Inside Source List Access List Number Pool Pool Internal Legal Address Pool Name
(4) Specify the internal port connected to the internal network in the port setting state:
IP Nat INSIDE
(5) Specify external ports connected to external networks
IP Nat Outside
Example 2:
In this example, the hardware configuration is the same, and the dynamic NAT address conversion function is used. The ETH port of 2501 is used as the internal port, and the synchronous port 0 is used as the external port. These 10.1.1.0 network segments use dynamic address translation. The corresponding internal legal address is 192.1.1.2 ~ 192.1.1.10
CURRENT Configuration:
Version 11.3
No Service Password-Encryption
Hostname 2501
IP Nat Pool AAA 192.1.1.2 192.1.1.10 Netmask 255.255.255.0
IP Nat Inside Source List 1 Pool Aaainterface Ethernet0
IP Address 10.1.1.1 255.255.255.0
IP Nat INSIDE
Interface serial0
IP Address 192.1.1.1 255.255.255.0
IP Nat Outside
NO ip mroute-cache
Bandwidth 2000
NO FAIR-Queue
ClockRate 2000000
Interface serial1
No ip address
Shutdown
NO ip classless
IP Route 0.0.0.0 0.0.0.0 Serial0
Access-list 1 permit 10.1.0 0.0.0.255
Line Con 0
LINE AUX 0
Line Vty 0 4
Password Cisco
end
3, multiplexing the environment where the dynamic address conversion is available:
The multiplex dynamic address conversion is first a dynamic address conversion, but it can allow multiple internal local addresses to share an internal legal address. This conversion is extremely useful to apply only to a small number of IP addresses but often more than the user's external network.
Note: When multiple users use an IP address, the external network uses uniquely identifying a computer by using the upper layer such as TCP or UDP port number through the router.
Dynamic address conversion configuration steps:
In the global setting mode, define an internal address pool
IP NAT POOL address pool name start IP address termination IP address subnet mask
Where address pool names can be set.
In global setting mode, define a standard Access-List rule to allow which internal local addresses can perform dynamic address conversion.
Access-List Number Permit Source Address Corner
The integer between 1-99 is 1-99.
In the global setting mode, the internal local address is set to establish multiplex dynamic address translations between internal legitimate IP addresses.
IP Nat Inside Source List Access List Number Pool Internal Legal Address Pool Name Overload
In the port setting, specify the internal port connected to the internal network
IP Nat INSIDE
In the port set state, specify the external port connected to the external network
IP Nat Outside
Example: Apply multiplexed dynamic NAT address conversion function. The ETH port of 2501 is used as the internal port, and the synchronous port 0 is used as the external port. 10.1.1.0 Network segment uses multiplex dynamic address translation. Suppose the company only applies for a legitimate IP address 192.1.1.1.
2501 configuration
CURRENT Configuration:
Version 11.3
No Service Password-Encryption
Hostname 2501
IP Nat Pool BBB 192.1.11 192.1.1.1 Netmask 255.255.255.0
IP Nat Inside Source List 1 Pool BBB overload
Interface Ethernet0
IP Address 10.1.1.1 255.255.255.0
IP Nat INSIDE
Interface serial0
IP Address 192.1.1.1 255.255.255.0
IP Nat Outside
NO ip mroute-cache
Bandwidth 2000
NO FAIR-Queue
ClockRate 2000000
Interface serial1
No ip address
Shutdown
NO ip classless
IP Route 0.0.0.0 0.0.0.0 Serial0
Access-list 1 permit 10.1.0 0.0.0.255
Line Con 0line Aux 0
Line Vty 0 4
Password Cisco
end
Router firewall configuration command
First, Access-List is used to create access rules. (1) Creating a standard access list Access-list [normal | special] listNumber1 {permit | deny} Source-addr [Source-Mask] (2) Create an extended access list Access-list [Normal | Special] ListNumber2 {permit | deny} Protocol Source-Addr Source-Mask [Operator Port1 [Port2]] DEST-AddR Dest-Mask [Operator Port1 [Port2] | ICMP-TYPE [ICMP-CODE]] [LOG] (3) Delete Access List NO Access-list { Normal | Special} {All | ListNumber [SUBITEM]} [Parameter Description] NORMAL specifies the rule to join the normal time period. Special Specifies Rule Add to Special Time. ListNumber1 is a value between 1 to 99, indicating that the rule is the standard access list rule. ListNumber2 is a value between 100 to 199, indicating that the rules are extended access list rules. Permit indicates that the message allows the condition to pass. Deny indicates that a message that is banned from satisfying the condition. Protocol is the protocol type, support ICMP, TCP, UDP, etc., other protocols are also supported, there is no concept of port comparison; there is a special meaning for IP, representing all IP protocols. Source-addr is the source address. Source-Mask is a source address communication, which is optional in the Standard Access List, and does not input, the representative library is 0.0.0.0. Dest-Addr is the destination address. Dest-Mask is a destination address communication. Operator [optional] port operator, support port comparison when protocol type TCP or UDP, supported comparison operations are: equal to (EQ), greater than (gt), less than (lt), not equal to (neq) or (RANGE); if the operator is Range, then you need to follow the two ports. Port1 appears when the protocol type is TCP or UDP, and a value (such as a telnet) or 0 to 65535 can be set for the keyword. Port2 appears when the protocol type is TCP or UDP and the type of operation is RANGE; the preset value (such as telnet) or 0 ~ 65535 can be set. ICMP-TYPE [Optional] When the protocol is ICMP, represents the ICMP packet type; can be a preset value of the keyword (such as echo-reply) or a value between 0 to 255. ICMP-CODE appears when the protocol is ICMP and does not select the set preset value; represents an ICMP code, a value between 0 to 255. Log [Optional] means that if the message meets the conditions, you need to do logs.
ListNumber is a value between 1 to 199, which is a value between 1 to 199. SubItem [Optional] Specifies the serial number of the rule in the access list of the delete serial number. [By default] The system defaults do not configure any access rules. [Command Mode] Global Configuration Mode [Use Guide] Rules of the same serial number can be seen as a type of rules; the defined rules can be used to filter packets on the interface, but can also be used to determine a message such as DDR. Is it interested in packets, at this time, Permit and Deny are interested or not interested. Use the protocol domain to expand the IP's extended access list to represent all IP protocols. Rules between the same serial number are arranged and selected in accordance with certain principles, which can be seen by the show access-list command. Examples Allow source addresses 10.1.1.0 networks, destination addresses 10.1.2.0 network WWW access, but not allowed to use FTP. Quidway (config) # Access-list 100 permit TCP 10.1.0 0.0.0.255 EQ WWW quidway (config) # Access-list 100 deny TCP 10.1.0 0.0.0.255 10.1.0 0.0.0.255 EQ FTP [Related Command] IP Access-Group II, Clear Access-List Counters Clear statistics for access list rules. Clear Access-List Counters [Parameter Description] ListNumber [Optional] To clear the number of rules of the statistics, if not specified, clear all the rules statistics. [Default] No statistics are not cleared. [Command Mode] Privileged User Mode [Use Guide] Use this command to clear the statistics of the current rules used, and do not specify the rule number to clear all rules. Examples 1: Clear statistics for rules that are currently 100 used. QUIDWAY # Clear Access-List Counters 100 Example 2: Clear statistics for all rules currently used. Quidway # clear access-list counters [related commands] Access-list 3, firewall enabled or disabled firewall. FireWall {enable | disable} [Parameter Description] Enable means that the firewall is enabled. Disable means that the firewall is prohibited. [By default] The system defaults to the firewall. [Command Mode] Global Configuration Mode [Use Guide] Use this command to enable or disable firewalls, you can see the corresponding results via the show firewall command. If a time-package filter is used, it will be closed when the firewall is turned off; the command controls the total switch of the firewall. When using the FireWall Disable command to turn off the firewall, the statistics of the firewall itself will also be cleared.
Examples Enable firewall. Quidway #firewall enable [related command] Access-List, IP Access-Group 4, FireWall Default Configuration Firewall When there is no corresponding access rule, the default filtering method. FireWall Default {Permit | DENY} [Parameter Description] Permit indicates that the default filtration property is set to "Allow". DENY indicates that the default filtration property is set to "disable". [Default] In the case of the firewall, the packet is allowed to pass the default. [Command Mode] Global Configuration Mode [User Guide] When the rule applied in the interface application does not have a message that a message should be allowed or disabled, the default filtration attribute will work; if the default filtration property is "allowed" , The message can be passed, otherwise the packet is discarded. Examples Set the default filtration properties as "allowed". Quidway #fireWall Default Permit 5, IP Access-Group Use this command to apply the rules to the interface. Use this command to delete the corresponding settings. IP Access-Group ListNumber {IN | OUT} [NO] IP Access-Group ListNumber {IN | OUT} [Parameter Description] ListNumber is a value of 1 to 199. IN expiration rules are used to filter packets from the interface. OUT indicates that the rule is used to filter packets forwarded from the interface. [By default] There is no rule to be applied to the interface. [Command Mode] Interface Configuration Mode. [Guide to Use] Use this command to apply the rules to the interface; if you want to filter the packets received from the interface, use the IN keyword; if you want to filter the packet forwarded from the interface, use the OUT keyword. One direction of an interface can apply up to 20 different rules; these rules are arranged in accordance with the size of the rule serial number, and the serial numbers are in front, that is, high priority. When filtration of packets, a method of finding the rules that meet the compliance will be used to speed up the filtering speed. Therefore, it is recommended that when configuring the rules, try to place the rules of the same network configuration in the access list of the same serial number; in the access list of the same serial number, the arrangement and selection order between the rules can be used for SHOW Access-List Command to view. Examples Apply Rules 101 to filters from the Packets received from the Ethernet port. Quidway (config-if-ethernet0) #ip access-group 101 in [related command] Access-List 6, settr settings or cancel special time sections. Settr begin-time end-time no settr [Parameter Description] begin-time is the start time of a time period. End-time is the end time of a time period, which should be greater than the start time.
[Default] The system defaults have not set the time period, that is, all of them are normal time periods. [Command Mode] Global Configuration Mode [Use Guide] Use this command to set the time period; you can set up the 6 time period at the same time, you can see the set time via the show timeRange command. If the time period has been changed in the case where a time period has been used, this modification will take effect at about one minute (the time interval of the system query time period). The set time should be a 24-hour system. If you want to set a time period similar to 8 pm to 8:00, you can set it to "Settr 21:00 23:59 0:00 8:00", because the two endpoints of the set period are within time, Therefore, it does not generate switching inside and outside the time period. In addition, this setting has also been tested by 2000 issues. Examples 1: Setting the time period 8:30 to 12: 00, 14: 00 ~ 17:00. Quidway (config) #settr 8:30 12:00 14:00 17:00 Example 2: Setting the time period to 8pm to 8 pm. Quidway #settr 21:00 23:59 0:00 8: 0 [Related Command] TimeRange, Show TimeRange 7, Show Access-List Displays Package Filter Rules and Applications on Interfaces. SHOW Access-List [All | ListNumber | Interface Interface-Name] [Parameter Description] All represents all rules, including rules within the normal time period and special time periods. ListNumber is a rule that displays the number ListNumber in the rule currently used. Interface indicates the rule serial number to display on the specified interface. INTERFACE-name is the name of the interface. [Command Mode] Privileged User Mode [Use Guide] Use this command to display the specified rules while viewing the rules filtering packets. Each rule has a corresponding counter. If you filter a message with this rule, the counter plus 1; through the observation of the counter, it can be seen in the configured rule, which rules are more effective, and which is basically invalid. You can view the situation of an interface application rule by using the show access-list command with the interface keyword. Examples 1: Displays a rule that is currently 100 currently used. Quidway # show access-list 100 Using Normal Packet-Filtering Access Rules Now. 100 deny ICMP 10.1.0.0 0.0.255.255 Any Host-Redirect (3 matches, 252 bytes - rule 1) 100 permit ICMP 10.1.0.0 0.0.255.255 Any Echo (No Matches - Rule 2) 100 denY UDP Any Any EQ RIP (No Matches - Rule 3) Example 2: Displays the application rule on the interface serial0.
Quidway # show access-list interface serial 0 serial0: Access-list filtering in-bound packets: 120 access-list filter out-bound packets: none [related command] Access-list eight, show firewall displays the firewall status. SHOW FireWall [Command Mode] Privileged User Mode [Use Guide] Use this command to display the status of the firewall, including whether the firewall is enabled, whether the firewall is used to use a time period package filtering and some statistics. Examples show the firewall state. Quidway # show firewall Firewall is enable, default filtering method is / 'permit /' TimeRange packet-filtering enable InBound packets: None; OutBound packets:.. 0 packets, 0 bytes, 0% permitted, 0 packets, 0 bytes, 0% Denied, 2 packets, 104 bytes, 100% permitted defaultly, 0 packets, 0 bytes, 100% denied defaultly. from 00:13:02 to 06:13:21: 0 Packets, 0 Bytes, Permitted. [related command] firewall Nine, show isintr displays whether the current time is within time. Show isintr [Command Mode] Privilege User Mode [User Guide] Use this command to display whether the current time is within time. Examples Display whether the current time is within time. Quidway # Show isintr it is not in time rantr it. [Related Command] TimeRange, settr 10, show timeRange Displays information of time package filtering. Show TimeRange [Command Mode] Privilege User Mode [User Guide] Use this command to display whether the current package is allowed to filter and set the time period. Examples Display information of time package filtration. QUIDWAY # show timeRange TimeRange packet-filtering enable. Beginning of Time Range: 01:00 - 02:00 03:00 - 04:00 End of time range. Packing filter function.
TimeRange {enable | disable} [Parameter Description] enable means that the enable time package is filtered. Disable means that it is forbidden to use a time period filter. [By default] The system defaults to disable time-package filtering function. [Command Mode] Global Configuration Mode [User Guide] Use this command to enable or disable the time period package filtering, you can see the display of the show time command through the show time command. After the time period package filtering function is enabled, the system will determine the rules (special) rules (special) (ordinary) rules (ordinary) according to the current time and settings. The accuracy of the system query time period is 1 minute. The two endpoints of the set periods are within the time period. Examples Enable time package filtering function. Quidway #TIMERANGE ENABLE [related command] settr, show timerange author blog:
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