【 Weak current College 】 Internet access is not fixed or the lack of a router memory capacity

In the LAN has just established a period of time, the network operation forms often compare fixed, this is because the network is equipped with is new, less network uses also match; however, after running a long time, LAN network fault occurs in the analogy, for instance, you cannot browse the Web site, the physical link dropping, slow network convergence, Internet functions not fixed anymore, and so on. Of these, some network problems due to a special clear sight, troubleshooting, processing up to often loosely analogous quietly; however there are some network problems is very strange, even ping test everything is normal, but the network transmission speed is abnormally slow, on this special kind of wrong, we will need to be more start, good troubleshooting, competence orientation problem causes, treatment of illnesses. This does not, network-man before encountering a fault with the Internet is not fixed, experience more, thoughtful and troubleshoot, aware of the defect is due to the lack of router memory capacity, provoked by the wrong element because this is rare, in troubleshooting the problem process more easily, now this article detours will eliminate the defects of the restoration process, for your companion reference exchange!

Case aware field

A unit of a subsidiary, total contains technology Department, Engineering Department, Sales Department, sales department that multiple departments, each sector and about 20 or so ordinary computers, those computers all resolved their respective sectors of BayNet brand ordinary exchange machine interface to a local area network of CISCO routers, each sector has its own separate tasks, each other cannot access each other, ordinary computer had the same task in a shared subnet, Exchange; however, units of file server, print server, Web server, and so on, is a direct connection to the router port, all departments have direct access to the computer, and they can also seek the router access Internet network. In order to ensure the safe operation of the LAN network, a subsidiary of network maintenance also in between the router and the Internet network, set up the TopSec hardware firewalls, to the entire organization's network access control and monitor the implementation of the security.

Normally, each of the departments of general computer works online, and these computers in various departments of the intranet, the mutual enforcement of sharing, exchange visits; at the same time, because the task required, the departments of Internet users almost daily to visit company's Web server, query, download the company's internal information. However, recently there has been a period of time, the network maintenance staff aware of users in various departments to access a Web server or Internet network, it often appears on the Internet is not fixed, which means that sometimes minute Internet speed, and time on the Internet is very slow, even for a moment can also become available on the Internet, you cannot fault with sight on the Internet.

Troubleshoot problems

Because of this defective sight exists in all sectors, the network maintenance measure this kind of scene usually and common client-side configuration of the system itself does not have any links that end with what elements will affect the entire LAN Internet fixed? network maintenance on defective sight again performed the analysis that the pitcher with attack with little time, you can follow, surf faster with slow, sometimes on the Internet can sometimes do not, this is no time the scene has a lot of trouble to be LAN network virus provoked, in reality many virus formation of network problems is to behave so no time. Assuming that confirm network virus is formed on the Internet is not fixed with elements, then network viruses are able to form a network of some major communication port data flow anomaly; according to this analysis, network maintenance resolution to use HyperTerminal order login to enter the LAN router background system, and then use the system comes with the function of the diagnosis, aware of the various communication ports in the local area network data traffic is not very large, this indicates the network virus and did not form a major port data transmission attack bottlenecks. Nevertheless, the network maintenance staff a little worried about not business as usual, the requirements of the tasks in all departments, immediately login to LAN network virus attack servers, device update network anti-virus software, and use it on your own computer systems Department performs a virus killing the operation, but it's best to did not get any results, it seems that LAN Internet access is not fixed with scene and network viruses didn't shut.

Thinking to network maintenance previously scanned individual AC port traffic and do not see any unusual circumstances, marked with the LAN and key data port does not exist, that is the Internet the bottleneck is not fixed with sight and bottleneck elements without a port. At the same time, the main communication port data flow size normal, but also does not exist in the local area network broadcast storm perhaps network loops, because the scene if they exist, we should see the output of the main communication port radio packet size should from time to time add to, the reality is no, which means that the Internet is not a fixed defects not by network broadcast storm or network loops scene provoked.

In the initial swept away the port bottleneck elements, network loop elements, elements and network broadcast Storm virus elements, the network still cannot eliminate defects, it makes a great network maintenance. Previously mentioned on the Internet is not fixed, network maintenance can be the understanding that the network connection is not secure elements, but now he won't suspect to network convergence factors, because the Internet is not a fixed wrong in almost every sector of the task will appear in the subnet, assumption that really is the network connection is not secure, it will not be able to all computers in LAN are both not secure vision.

There can be a network equipped with its own function is not fixed, the formation of the Internet without fixed sight? think summer hours, some equipped with bad due to heat, making capital as task functions, often appear on the Internet dropped or is slow, the network maintenance can be inferred from the local area network routers or Exchange machine overheat, making capital as task function is not fixed. Thus, the network maintenance immediately left the company in the engine room, first viewsNotes the router, AC machine lights form, aware that everything works, then hand touch those equipped with exterior temperature, without anyone to have any exceptions.

In a famous cannot, network maintenance log into LAN resolution firewall system, check some of these works form information, to see if there's nothing suspicious sites. Make him feel very unexpected things, network maintenance see LAN firewall has recorded many IP addresses as host-address 0.0.0.0, that 0.0.0.0 is what kind of host address? experience online search, network maintenance staff aware of the address is a Windows system for all unknown IP address configurations, contains the network card is equipped with a resolution of the acquisition of the address of the dhcp, pppoe, IP addresses, and other non-native specified IP address; the address 0.0.0.0, also on behalf of the whole zero network, it can assist the router sends the routing table cannot query packets. Hypothetical configuration all zero network route, the routing table cannot query packets will be sent to all zeros network routing. Resolved topmost painted, network maintenance personnel that the address is an address that does not exist, then the end is what elements make the external network and on a basic LAN does not exist in the host executing communications? assumptions are really outside the network and the address from time to time perform address 0.0.0.0, then outside the network packet is how to get to the local area network?, because the unit LAN firewall has been configured to block the use of clearly false address of a host implementation of the communication?

Handling faults

Experience further inspection firewalls, network maintenance see 0.0.0.0 address is not performing any operation, their communication really is firewall prevented? is the LAN was unlawful attack, attack Pack after entering the internal network, the IP address 0.0.0.0 addresses by posing as? to the reality is that the IP address 0.0.0.0 connected host has failed to perform any communication operations, unlawful attack packets even in trying to attack intranet, without success, so it will not be formed on the Internet without fixed vision; to this end, the network maintenance judgment does not exist outside the network attacks, the address 0.0.0.0 must come from the internal LAN, this can not be the IP address is how to occur? consult relevant information again on the Internet, network maintenance staff aware of some of the major network equipped with memory capacity can be discarded in the communication process, some packets of information to form certain Internet content cannot be effectively combined with, as prone to some address 0.0.0.0.

In accordance with the actual analysis, the network maintenance staff is able to deduce the 0.0.0.0 address from the intranet, and the address is to be given in exchange for a local area network or router memory capacity is not provoked. Because the Internet is not a fixed problems in each sector, network maintenance measure questions mostly out of tasks pertaining to the subnet router equipped, so that a preliminary resolution remote log on to the LAN interface router background system, in the remote logon process, the network maintenance staff feel to the logon speed clearly dull, looked really doubt the router is equipped with. After that, he used a Console control cable directly linking to your router, check their background system memory usage patterns, aware of the amount of memory that is equipped with really lacking, it is clear in the Internet during the peak period, router memory capacity more lacking, so naturally to the router does not forward the data information, which is precisely one of the departments of reasons the Internet.

Find the wrong reasons, network maintenance immediately restart a router system, aware of the various sectors of the online forms immediately reverted to normal, then again monitoring router memory capacity, aware that memory usage is also often larger, it seems to be the real deal with questions, but also have to qualify the router is equipped with, or after a period of time, and you want to restart the router system.