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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25
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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 ...
17
votes
8answers
4k views

Mouse cursor jumps around when using RDP

We have over 350 users complaining that their mouse cursor keeps jumping around when typing. It seems like it's happening when the protocol is starved for bandwith, but I'm not quite sure yet. If it ...
10
votes
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 ...
8
votes
5answers
734 views

Blocking BitTorrent

How can one block, or severely slow down, BitTorrent and similar peer-to-peer (P2P) services on one's small office network? In searching Server Fault I wasn't able to find a question that served as a ...
8
votes
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 ...
6
votes
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!
6
votes
2answers
10k views

How do you configure QoS for Skype?

On our office network (26 people), some users have complained of poor Skype call quality, particularly in the upstream direction. I wanted to ask, how do I identify Skype traffic, considering that it ...
6
votes
3answers
268 views

Linux QoS: bulk data transmission during idle times

How would I do a QoS setup where a certain low-priority data stream would get up to X Mbps of bandwidth, but only if the current total bandwidth (of all streams/classes) on this interface does not ...
5
votes
4answers
2k 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 ...
5
votes
2answers
637 views

nginx clobbering sftp traffic during peak times - is tc the answer?

This is probably a continuation of my previous (unanswered) question because the underlying cause is probably the same. I have a Linux server with nginx and sshd running on it. It's on a shared ...
4
votes
7answers
21k views

How can I block Spotify on our company network?

How can I block Spotify on our company network? Unfortunately it's killing our bandwidth and the effect is really serious.
4
votes
2answers
2k views

3 WAN and a Cisco Router - PBR, QOS, Load-Balancing

I have a cisco router with 4 ethernet interfaces, scenario is as follows : 2 x Dedicated Leased Lines (2MB and 4MB) 1 x Business Class DSL 10MB 4 3COM L2, Switches, connected to a Core Switch (3COM ...
4
votes
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 ...
4
votes
1answer
823 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 ...
4
votes
1answer
579 views

Traffic shaping: tc filter catch all filter

How Can I configure a "catch all" filter with tc filter? I tested with the following code but it gave me the error: "Unknown filter "1:100", hence option "protocol" is unparsable": tc filter add ...
4
votes
2answers
1k views

How to QoS NFS?

I have the following NFS-based storage setup: Computes nodes are Linux. The NFS servers are Solaris. A not-so-important user runs a bunch of read intensive jobs on a subset of the compute nodes. As ...
4
votes
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 ...
4
votes
0answers
470 views

MasterShaper alternative [closed]

I'm looking for an alternative to MasterShaper, something possibly web-based which could allow me to manage QoS easily. Actually MasterShaper still looks supported, but would like to understand if ...
4
votes
2answers
493 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 ...
3
votes
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?
3
votes
2answers
357 views

Linux qos: tc DRR qdisc does not work

There is tc queue discipline DRR(Dificite Round Robin) . It has same capabilities, as HTB, but instead of using buckets, filled with tokens, it just assignes every queue some Dificit Counter. On ...
3
votes
2answers
946 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 ...
3
votes
1answer
3k views

QoS on Cisco ASA 5505 by VLAN/subnet

My ASA 5505 has three VLANs. One connected to the internet called outside, one for our office called office (which connects to the corporate VPN) and one for a publicly accessible resource-centre. ...
3
votes
4answers
6k 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 ...
3
votes
1answer
2k views

Rate Limiting with HP ProCurve 5406 QOS

Is it possible to enable an absolute value rate limit using QOS on a HP ProCurve 5406 switch for a particular IP address on a specific port? We have a 10Mbps head end connection for multiple ...
3
votes
5answers
669 views

QoS configuration for a medium ISP

What is the best Linux-based QoS platform to implement a configuration where all 256Kbps DSL clients (all belong to the same IP range) get a guaranteed speed of 200Kbps with single QoS rule?
3
votes
1answer
1k views

Cisco ASA 5510 Time of Day Based Policing

I have a Cisco ASA 5510 setup at a boarding school. I determined that many (most?) of the students were downloading files, watching movies, etc, during the day and this was causing the academic side ...
3
votes
1answer
1k views

Limit torrents via QoS on router

I have a very simple linksys router at home with basic support for QoS. We have a problem when everyone is at home that web browsing becomes unusable. I've tracked it down to too many people ...
3
votes
2answers
189 views

Can TC (Linux Qos Utility) limit bandwidth usage of target applications?

We have many applications running on the same server machine which is inside a network of servers. We want limit the bandwidth of our applications to specific value. So here are some choices: ...
3
votes
2answers
881 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
votes
2answers
6k 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 ...
3
votes
0answers
112 views

IOS QOS service policy pass-through on a tunnel interface

I have some SIP phones on one network that go through an IPIP tunnel to get to the server. I've setup QOS rules to watch for appropriate VOIP traffic as follows: class-map match-any class-voice ...
3
votes
1answer
518 views

Qos/iptables? for vonage and openvpn? … or something else?

I have a small home office setup. I use google voice and vonage for phone calls. Please see the diagram -- I know this not the ideal but since my cisco switch (3550) packed up so this is the only ...
2
votes
3answers
1k views

VLANs using one managed switch or link router to unmanaged switches?

I'm the resident IT guy in an office with about 20 workers, amongst 3 separate companies who sublet an office. We are wired with 24 ethernet ports dotted around the offices that all lead to a patch ...
2
votes
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 ...
2
votes
3answers
2k views

Making iptables recognize youtube streams and large files

I use Ubuntu server 10.04 with the stock kernel as a NAT router. I use iptables and tc to do port based traffic prioritization. It is working fine. I have given http higher priority. So my network ...
2
votes
3answers
2k views

QOS on ubuntu server

I want to run the following script on ubuntu server. eth1 is NAT interface, and eth2 is the WAN interface which has a static public ip: TCA="tc class add dev eth2" TFA="tc filter add dev eth2" ...
2
votes
2answers
869 views

how limit the number of open TCP streams from same IP to a local port?

i would like to limit the number of concurrent open TCP streams from the the same IP to the server's (local) port. Let's say 4 concurrent connections. How can this be done with ip tables? the ...
2
votes
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 ...
2
votes
1answer
152 views

Is there an effective way to monitor the load on each switch?

We have about 200 IP phones in our building and I realize we got more complaint about the phone quality after we switched our internet from 50Mbps to 200Mbps Up/Down. I know there's a possibility ...
2
votes
1answer
770 views

How to set up QoS VoIP priority on linux

I am configuring a small network and my idea is to use a linux server as a proxy it will be serving local services to the clients and it will have also a squid server as a caching server for speeding ...
2
votes
2answers
403 views

QoS on DD-WRT Questions

I have a question about quality of service (QoS) on linux (DDWRT specifically). Here's my setup: Recent version of DD-WRT 120 kbytes/s up and 2mbytes/down Traffic limited to about 80% of stated ...
2
votes
4answers
3k views

Is there some advanced traffic shaping frontend for linux?

If you ever worked with Mikrotik routers, you probably got used to 'simple queuing', a very simply manageable list of IP->speed rules. I guess other router OSes have something similar, for those who ...
2
votes
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 ...
2
votes
1answer
252 views

Load balancing SDSL + ADSL with Zyxel USG-100

I have a Zyxel gateway/firewall, and two Internet connections : SDSL (4MB up, 4MB down) and ADSL (15MB down, 1MB up). I'm trying to configure my Zyxel to use the two connections, and to use the SDSL ...
2
votes
1answer
79 views

PIR/max-burst ignored message

After I typed the following police command for a type qos class on a Cisco Nexus 7000 switch: police cir 8 kbps pir 8 kbps I get the following message: Note: pir/max-burst ignored Can someone ...
2
votes
1answer
467 views

Cisco DSCP based packet drop

On a Cisco router, when setting up a policy-map to shape traffic and drop packets based on DSCP (such as the example below), which class of packet will be dropped first: DSCP 0 or AF13? DSCP AF13 is ...
2
votes
1answer
665 views

Mediatemple (dv) kmemsize, privvmpages, tcpsndbuf QoS alerts [closed]

I'm on a (mt) (dv) base 3.5 server and am running ~20 small sites and I keep running into memory issues: cat /proc/user_beancounters Version: 2.5 ...
2
votes
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 ...
2
votes
1answer
633 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 ...