Quality of service is the ability to provide different priority to different applications, users, or data flows, or to guarantee a certain level of performance to a data flow.

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728 views

How the big guys monitor their servers?

I'm wondering what software the web scale guys are using to monitor their n arrays of servers in the server farm(s). What does facebook, twitter, digg use? How google does it? I'm looking for a ...
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3answers
60 views

Recommended system self test tool (what software should I use)?

We have a setup of: ~20 nodes on EC2 Several AppEngine deployments Several small locally hosted nodes All these machines represented 1 distributed system that does "cool things". The problem is ...
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1answer
2k views

Traffic prioritization with Linux htb doesn't work, why?

I'm a Linux QoS newbie and I'm trying to learn how it works by using the docs at lartc.org as reference. My first goal is a modest one: I want to assign a higher priority to UDP outgoing traffic, but ...
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3answers
378 views

Distinguishing between types of P2P traffic on a Packet Shaper

I attend and work at a university where we have a packet shaper (an old Packeteer -- 3-ish years old or so) which relegates P2P traffic to the lowest priority in the queue in order to prevent P2P ...
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468 views

Squid Reverse Caching Proxy with ACL and Delay Pools

I have to configure a Reverse Proxy Caching Squid box to do: Define Content groups, e.g. images containing gif, png, ico, jpg, jpeg, etc Audio containing mp3, wav, ogg etc Video Archives Binary ...
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1answer
333 views

Using L7 to classify pcap data

I've recently become familiar with the Layer 7 Filter project, and it's ability to classify protocols is quite interesting. All of the information about its use, however, concerns using the filters ...
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1answer
93 views

QoS in serviced offices

We recently have encountered a problem on our two shared lines provided by Regus in a serviced office. When there is download on either connection it renders the Internet unusable for anyone. I've ...
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2answers
999 views

Block Skype on Cisco IOS

I'm trying to block skype via policy routing but it's not working ... here's my configuration: class-map match-any block match protocol skype policy-map QoS-Priority-Input class block police ...
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4answers
1k views

Cisco IOS QoS prioritize SSH but not SCP

How can I prioritize ssh traffic to ensure low-latency but throttle SCP file transfers? I'm looking for a solution that is not host specific so I don't have to add lists of IP addresses. Thanks!
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2answers
809 views

QoS - split bandwidth across all IPs during high load

We have a Linux-based router which is currently working fairly well, but our network only has a 1.5 mbps incoming connection. The network is small, but during high load periods some systems can end up ...
3
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2answers
908 views

Cisco QoS Guidance

I have a 10M connection to the internet that is hooked into a 100M port. I am getting started with QoS, and am hopping for a little guidance on setting it up on a Cisco 3825 router. Right now I am ...
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2answers
5k views

QoS for Cisco Router to Prioritize Voice and Interactive Traffic

I have a Cisco 891W NATing Voice and Data to the internet over a 10mbit/2mbit connection. Voice traffic gets degraded when I upload large files. Pings time out as well. I tried to configure a QoS ...
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0answers
258 views

Troubleshooting iptables and configuring it to drop the priority of long-term connections

I'm somewhat familiar with the general concepts of iptables, and would like to learn it in more detail. I'm hoping that my learning experience can also be useful. The situation: I'm running dd-wrt ...
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1answer
604 views

Setting reply priority on Wifi network with QoS?

When using a Station and Access Point that support QoS over Wifi, is it possible to set the priority (= Traffic Identifier = TID = QoS channel) of the reply? For example when sending a ICMP ping ...
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2answers
730 views

QoS / PBR Routing Questions

I have a 50Mbs Satellite link and a 10Mbs Microwave link supplying a very remote location. Behind these links, I have a 6,400 seat network - with about 3,000 signed in at any one time. My goal is to ...
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4answers
947 views

MediaTemple tcpsndbuf QoS Alerts

I'm hosting with MediaTemple on a (dv) Dedicated-Virtual 3.5 server. My site consists of a Wordpress blog, some custom PHP pages (nothing too intense), and I server 500-700 unique visitors per day. ...
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4answers
4k views

Does anyone really understand how HFSC scheduling in Linux/BSD works?

I read the original SIGCOMM '97 PostScript paper about HFSC, it is very technically, but I understand the basic concept. Instead of giving a linear service curve (as with pretty much every other ...
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1answer
1k views

Sharing Bandwidth and Prioritizing Realtime Traffic via HTB, Which Scenario Works Better?

I would like to add some kind of traffic management to our Internet line. After reading a lot of documentation, I think HFSC is too complicated for me (I don't understand all the curves stuff, I'm ...
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2answers
128 views

How can I stop one virtual iis site from drowning out all the others?

I have about 20 IIS web sites on one Windows 2003 server. One of the websites is for downloading product updates. What methods/tools are available to me to ensure that the one does not kill the ...
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2answers
267 views

Validity of my basic Performance Testing Results on a LAN

Networking is not my main job and i am hoping you guys can comment on my test procedure so far to identify PCs best to host a few voip softphones. Our 100Mb LAN comprises of 40 Win XP/2000 PCs and a ...
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4answers
5k views

What are good and bad jitter times for a LAN

Ive just ran jperf (frontend to iperf) on our network between 2 workstations, its recorded jitter between 0.033ms and 0.048ms. Is this good or bad? Are there more variables that i would need to ...
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2answers
117 views

What switch spec would i need to support 50 SIP extensions

Were a call centre and thinking of moving our phone system to a voip based setup. It seems most advice advises keeping this network seperate from the standard LAN, what switch specification would be ...
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1answer
723 views

What free utility can I use to test LAN performance and quality?

I want to test a LAN for speed and reliability, I wanted to use qcheck but it won't instal on any of our XP systems. What other tool could I use? Is there anything with voip tests that is free? Does ...
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3answers
2k views

How do I use the `tc` command to give the 1st queue priority?

Lets say I have 3 queues (# indicates data): Q1: (in)[ ###](out) Q2: (in)[ #####](out) Q3: (in)[ #############](out) Lets say I put all my ICMP packets in Q1 and all the ...
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1answer
88 views

Load balancer + CPU load manager to handle SIP connections?

I no longer have a landline and subscribed to a VoIP provider to have a landline phone number. I prefer to use a softphone (EyeBeam, the commercial version of XLite), but there are times when a call ...
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1answer
2k views

Marking packets with iptables with a NAT

I have to write bash scripts for a router to control bandwidth limitation for a given user on a given domain name. For this, I'm using iptables to mark the packets incoming from a restricted domain ...
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1answer
3k views

How to use virtualbox to simulate a sub network with the host as router?

I am currently working on QoS router functions using iptables and tc on Linux. I would like to use virtualbox to simulate a computer plug on my router (The router would be the host) Physically, I ...
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6answers
3k views

Rate limiting an internet connection per user

I've got a friend who has a "rent-by-room" property and includes internet access as part of this. However some tenants are somewhat hogging the internet (i.e. constantly downloading). I was ...
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4answers
427 views

Prevent a download to saturate all bandwidth on Linux

In Linux, a single download can use all available bandwidth, so that any other connection can't be started. (e.g. if I am downloading updates, I can't surf the web at the same time) Is there a way to ...
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5answers
2k views

How should I set up a gateway to restrict internet traffic in a college dorm?

OK, like all college IT departments, we've been battling P2P abuse and trying to figure out how to effectively mitigate it's impact on our network infrastructure.... And then we find out TODAY that ...
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5answers
3k views

QoS for very basic LAN/WiFi network: Do I need SmoothWall or OpenWRT or just good advice?

Here is the basic situation/topology of the network I manage: Residential, but we are a co-op, so we have a business-class contract with ISP. The residents are college students, so there is quite ...
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3answers
8k views

QoS basics on a Cisco ASA

Could someone briefly explain how to use QoS on Cisco ASA 5505? I have the basics of policing down, but what about shaping and priorities? Basically what I'm trying to do is carve out some bandwidth ...
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2answers
1k views

Best tool for QoS testing

The problem is that, i cant find good tool for QoS configuration testing(linux). I have some switches and configured QoS on them. Installed two PC's with wireshark for watching whether switches are ...
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3answers
2k views

Are there simpler ways to do traffic shaping in linux besides tc?

I read lartc but I don't feel I need such a complicated solution for simple needs. One of such simple use cases is to limit a specific process' available bandwidth, upstream or downstream. How can I ...
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5answers
2k views

What is QoS and When to [not] use it?

As the title states! What is QoS When is it good to use it? When is it not good to use it?
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4answers
1k views

Traffic Management recommendations [closed]

What's your strategy towards traffic prioritization/management. I am not really to just get a list of packet shaping solutions. Instead, I would like to get recommendations about traffic management ...
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2answers
486 views

Linux TC / Policy Routing tools

In addition to a really good firewall Linux has a builtin advanced routing and traffic shaping (lartc). There are many applications (firehol, firestarter, etc) to make the creation of iptables ...
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11answers
2k views

SOHO - throttle bittorrent traffic from problem users

I manage the network in a small office (SW dev is my "real job"), and there are a couple of users who beat the hell out of our internet connection by running bittorrent. Between the almost crippling ...