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Questions tagged [rate-limiting]

In computer networks, rate limiting is used to control the rate of traffic sent or received on a network interface.

Traffic that is less than or equal to the specified rate is sent, whereas traffic that exceeds the rate is dropped or delayed. Rate limiting is performed by policing (discarding excess packets), queuing (delaying packets in transit) or congestion control (manipulating the protocol’s congestion mechanism). Policing and queuing can be applied to any network protocol. Congestion control can only be applied to protocols with congestion control mechanisms, such as the transmission control protocol (TCP).

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Postfix and smtpd_client_rate_limit to detect compromissed accounts

Some of our clients are administrators who need to send corporative messages to no more than 300 clients, specifying all of these clients together in the "To:" fields, instead of individual messages for each one. After that, postfix will "adjust"…
ABu
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nginx rate limiting: unknown directive limit_req_zone

I'm trying to set up a rate limit for bots using my website, but if I add limit_req_zone $binary_remote_addr zone=one:10m rate=1r/s; or anything of the sort to /etc/nginx/nginx.conf in the http block, before the includes I get user@srv:~$ sudo…
glasspill
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Protect a public-facing PostgreSQL server against abuse

I have a Postgres database containing public information that I'd like to expose to the internet, for anyone to use. What steps can I take to prevent: Excessively expensive queries that could hog resources, preventing access by others Queries that…
Steve Bennett
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DNS query limit WinServer 2008R2

Situation: I am currently seeing a huge wave of incoming DNS requests arriving in burst of around 85 queries per 2-3 seconds from one IP. Then another IP sends a new wave and so on (currently my DNS service is turned off, so that it does not take…
Philip Allgaier
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Mail server - limit connections on port 25 to 1 PC alone

I have a situation where only one PC on a network (network is behind a single public IP address) can connect to the mail server on port 25 (send out emails using Outlook, perform successful telnet test). Previously, all the systems could, all of a…
Ugorji Nnanna
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Reasonable rate limiting settings with PF firewall

I have the following settings in my pf.conf to dissuade abusive clients (I get a few a day that are obviously just scraping content indiscriminately and slow everything down): pass in on $ext_if proto tcp to { $loadbalancer1_int } port $web_ports…
onyxrev
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Easy Apache module to throttle requests based on machine load?

I have an Apache server that is serving a django application with mod_wsgi. I'm wondering if there is a simple way to throttle requests at the apache level based on the machine's load. Ideally I want an apache module that if the load is below a…
Amandasaurus
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Best way for automated ban / throttle of aggressive clients on a Linux / Apache webserver for a period of time?

I notice occasional spikes on my server load and when I check access logs I notice a pattern for some automated forum poster that tries to repeatedly access a comment/reply URL. What would be the best way to throttle /ban these for a few minutes /…
giorgio79
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How to tune Linux kernel to withstand DDoS? (HAProxy)

Please do not reply with "this is not possible", as it's waste of time. I am developing cloud appliance and I have a valid reason to protect this layer against DDoS, and there are few companies doing the same, so please dont tell me that I dont have…
Andrew Smith
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How can I prevent postfix from sending thousands of emails?

I have a Django installation that is configured to email administrators (five of us) whenever an error occurs. All of the generated emails are directed to postfix and then on to the mail server for distribution. Unfortunately, we encountered an…
Huuuze
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Know a way to parse Speed Test results?

I like SpeedTest.net, but what I'd really like to do is put a graph in cacti, run a speed test every half-hour, and graph the results (maybe running it three times each time and averaging it). I can do the cacti part, but I need a script (perl,…
Tom Ritter
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Block UDP traffic by rate/string-match on Windows 2008

I am administrating a Windows 2008 server (64-bit). It is being subjected to a focused set of DOS attacks where UDP packets are sent to a specific port and contain a specific string. What I need to do is rate-limit UDP traffic to that port on a per…
T3RCX
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Rate Limiting Outbound E-mail Message on a WHM/cPanel/Exim/CentOS 5 system. .

I have a client who is using Interspire e-mail marketer to send out his e-mail messages, and this guy sends something like 100,000 e-mails per session and does this around 3-4 times per month. He's one of my hosting clients, and I'm trying to…
Eric
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What is the main difference between iptables and EC2's "security groups"?

If I block traffic via a security group, I assume I don't have to pay for it. But if I block traffic via iptables installed on my server then I assume it would be me that pays for any incoming traffic I blocked. Are there things iptables can do that…
darkAsPitch
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How can I use fail2ban to block scrapers?

I have a media site and problems of users coming along and scraping all of the content.I placed a invisible URL on the page to catch spiders that immediately blocks the ip, but some people have figured out the URL scheme and are creating their own…
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