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How to avoid network downtime and what are the top reasons for this?

Let's see what are the most common causes of network downtime, and what can be done about them?

Issue: Hardware single points of failure
Solution: Try to minimize single points of failure. When they're unavoidable, make sure broken hardware can be replaced quickly.
If it's impossible to connect servers to multiple switches, be able to replace a broken switch with another one that has an identical configuration. So either use those switches in their default port/VLAN configuration, or set up a spare switch with an appropriate basic configuration in advance so simply replacing the hardware is enough to restore connectivity.

Issue: Routing protocol problems
Sometimes, for some reason, the packets are lost, but the BGP doesn't notice that there's a problem, so traffic is flowing towards the black hole rather than be rerouted.
Solution: One way to detect this problem is to monitor reachability of key remote services. Another is looking at total traffic, which will be much lower than usual in the presence of a black hole. Once detected, recovering from routing black hole affecting one ISP is very simple: shut down the BGP session towards that ISP until they've fixed the problem.

Issue: Routing problems caused by software bugs
Solution: It is useful to have equipment from different vendors, so that if one device is affected by a bug, the other one isn't.

Issue: Power supply problems
Solution: Having some kind of backup power is key. Also all network components must have redundant power supplies connected to different circuits, so they can keep running when there's a failure or maintenance on one feed. Make sure one circuit can provide adequate power by itself, and that the circuits have as few components in common as possible. If it is not possible to ensure redundant power supply, it's important to have two components that provide backup for each other connected to different power circuits, so if one circuit goes down, that doesn't take out both devices.

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single touch to open and close the window is not working


Check settings in the Mouse or touchpad software. If this is a recent event try a System restore to a date before this issue. It may be a hardware failure. Take a look at Dell Support, it may be a common issue: http://www.dell.com/us/p/xps-13-l321x/pd Have you done ANY updates recently?

Apr 07, 2013 | Dell Ultrathin Xps 13 L321x I7-2637m...

1 Answer

What Is Network Failure


A network which contains many network components of both hardware and software can incur failures due to one (or even multiple) of its contained components incurs a failure. Ranging from the largest to the smallest and from hardware to software, network failures can be divided into the following categories:

  • Control plane failure:this type of failure is mainly related to software, i.e., network control plane software. For example, in a GMPLS-based network which is made up of a control plane and data plane, the control plane failure would lose the control of the data plane, which means that we cannot establish new service connections, or terminate or modify an existing service connections within the data plane, even though the existing connections can still perform normally to carry user's data. In other type of networks such as IP networks, the control plane failure can be even more serious. For example, the pollution of IP lookup tables at some routers would cause all the IP traffic on these nodes difficult to be forwarded. Similar stories occur for viruses attacking IP routers. They disable the IP networks through disabling IP network control plane.
  • Subnetwork failure: this is a type failure occurred with a regional subnetwork that commonly shares a risk, e.g., a region that has high occurring frequency of earthquake. In addition, some large disasters such as flooding, tsunami, etc. can also disable a regional subnetwork.
  • Node failure: this is a type of failure occurred with a single network node. The reasons for this kind of failure include accidents or disasters at a network operational center, such as power shutdown due to fire, flooding, etc.
  • Network card failure: network card failure is a type of failure under the umbrella of the node failure type. Rather than the shutdown of the whole switch node, sometimes a failure can occur only with a network interface card. For example, the failures or faults such as a laser outage, fault of a circuit board, or software bugs, etc. can also contribute to a network card failure.
  • Link failure: link failure in general is the most common network failure that occurs due to fiber cut.
  • SRLG failure: SRLG failure is a generic concept to define all types of network failures whenever a common SRLG incurs a failure. Here a SRLG can be a fiber link, node, subnetwork, or control plane, etc.
  • Single failure and multiple failures: in general network failure implies a single network failure because network failure normally seldom occurs. However, under some situations, there can be more than failure occurring with a network. This kind of situation is called multiple failure, example, dual failures and triple failures. For a network, planning for full recovery of multiple failures generally requires much high protection capacity than that of purely for a single failure.

    Jan 04, 2011 | Samsung J700 Cellular Phone

    1 Answer

    failure in transmision


    So are you saying you have two different wireless Access points for a small network? Could they be interfering with each other? I looked up the products and they seem a little more complex than a small network might need.

    Maybe try only one at a time, and since you can connect via wire, you should be able to access the router/abp via the web page, and see what channel it is on and the ssid, and verify that the wireless features are on. After that, try rebooting the apb, waiting a few minutes, and do a search for wireless networks.

    I would not expect a random failure on both transmission and reception, so breaking it down to each component may help. Can any wireless network search see either ap when only one is active?

    I wold recommend a single, simple consumer wireless router, dlink or netgear maybe, as they have seemed a bit more straight forward to me than the trendnet faqs I pulled up. If the investment is sunk, trying the above may help narrow the problem.

    May 29, 2008 | Trendware TEW-410APBplus 802.11g/b...

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