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I am using an LTE dongle for internet connections.

Yesterday after some reconnections I couldn't reach any SE sites.

I checked with Tor and could connect. It appeared that I got some IP address that had been banned by SE.

I reconnected, got another IP and it all started working. Today there were some problems with the ISP, and the dongle reconnected a few times. Finally I got some banned IP again.

Is there a policy that has some time limit for banning this kind of pools? Otherwise, banning many IPs will affect normal users.

The question is about IP pools used by wireless or other ISPs for dynamic IPs. Banning those permanently makes no sense, because these IPs don't stay long with one user.

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    There are several routes that are governed by IP throttling on the HA-proxy, IIRC. Some /most throttles that you trip by accident last for 2 minutes but might adjust dynamically. If your IP or IP block shows up too often in the log you might be in for a special treatment. the few "regular" users that might be impacted by this doesn't warrant the abuse done by the foul players. I do know that there have been incidents where whole IP ranges where blocked for a reasonable amount of time. – rene May 31 at 10:32
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    I would guess the powers that be might not want to share that since it would be useful for spammers. Sounds frustrating – Journeyman Geek May 31 at 10:53
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    @JourneymanGeek I don't expect that someone publishes all the rules. But I expect that someone tells if it is tracked properly. Just banning these IPs e.g. for spamming is a bad idea. Spammers simply change IPs. And also spam is not that serious a problem here, because there are other ways of dealing with it that are effective enough. – Pilot6 May 31 at 11:00
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    And also spam is not that serious a problem here, because there are other ways of dealing with it that are effective enough. Can you elaborate how spam is not a serious problem? – rene May 31 at 11:17
  • @rene It is well known that here at SE users moderate the site. So spam posts are caught in seconds or a few minutes, flagged and deleted. It doesn't require moderators' effort. – Pilot6 May 31 at 11:23
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    While that is true, only a very small amount of spam actually makes it to the site. The IP blocks among other tooling is instrumental in that. Removing / lowering that shield might open a floodgate that can't be handled by mods, normal users with the help of projects like the SmokeDetector. – rene May 31 at 11:31
  • Now caught another banned IP in 31.173.25.xx. It is annoying when you have to find an IP that works. – Pilot6 May 31 at 13:22
  • @Pilot6 well this range is heavily used by Russian spammers: cleantalk.org/blacklists/as31213. – Shadow Wizard Wearing Mask May 31 at 14:22
  • Anyway, I would like to believe the IP ban is not permanent, but rather updated manually as required, so it shouldn't be too big a problem, for normal users, who don't change IP range a lot. – Shadow Wizard Wearing Mask May 31 at 14:24
  • Well, it is one of the largest Russian wireless operators MegaFon. Obviously spammers use it, but banning dynamic IPs there doesn't do anything good. – Pilot6 May 31 at 14:25
  • SE isn't a big company, it can't handle wave of 10000 spam posts once already posted. And without low level blocks like this.... it will happen. – Shadow Wizard Wearing Mask May 31 at 14:27
  • My point is that banning specific addresses from a dynamic pool doesn't make any sense. It takes a few seconds for a spammer to reconnect and get another one. If it is a short ban, it is OK, but a long one is useless. The next day this address will be used by a normal user. – Pilot6 May 31 at 14:30
  • It makes sense if it works. The negative side effects are unfortunate, but you can't state it doesn't make sense if it helps keeping the bad guys out. Perhaps there's a system doing the same with less side effects that would make more sense, but that doesn't mean the current one is wrong altogether. – Mast May 31 at 14:53
  • @Mast It doesn't keep bad guys out at all. They will use all IPs until the whole range is banned and then move to another ISP ;-) – Pilot6 May 31 at 14:55
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A quick clarification, there are two types of IP bans that we use: a rate limit and a block. IP addresses very rarely end up fully blocked, and it takes an excessive amount of abuse from an IP in order to end up blocked.

The vast majority of IPs end up temporarily rate limited. Essentially our system detected an unusual number of requests coming in from a single IP and stopped further requests from it temporarily. These rate limits usually disappear within a minute if it was just a one-off glitch or something (such as refreshing the page many times in short succession).

However, there is no set time limit for how long a rate limit remains in effect - it completely depends on the people currently using the IP and how many suspicious requests we continue receiving.

Without more detail of the specific error you saw, I can only guess that you got hit by the rate limiter, as it is the most common thing people see when they've recently experience reconnect issues and unintentionally sent a bunch of requests to us.

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  • I don't think it is a rate limit. It looks like some IPs are more or less permanently blocked because of some abuse. But the problem is there is a big pool of addresses that is owned by a cell phone company. They are assigned dynamically to users connected by phones or 3G/4G modems. I believe that spammers really use this provider and really abuse. But the problem is that the addresses are provided to certain users for a very limited time. So banning them permanently affect normal users and doesn't really affect spammers. – Pilot6 May 31 at 15:50
  • I didn't write down the addresses. I caught 3 of them. The last one was 31.173.25.35. Now I am connected from the same pool 31.173.87.28 and this one is OK. – Pilot6 May 31 at 15:52
  • If you were blocked by us you would be landing on a Stack Exchange page that clearly identifies whether you are being stopped by a block or rate limit. If you are seeing something else, then you are being blocked at some point before ever reaching our servers. – animuson May 31 at 16:01
  • I couldn't reach the site and got no message. When I got that 31.173.25.35, I couldn't connect to any SE site at all. But after I got another address, I could. But I could ping SE sites from 31.173.25.35. – Pilot6 May 31 at 16:03
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    If you're seeing no message, you are probably being dropped by Fastly, not us. I don't personally know anything about how their IP blocking works, and if they are blocking an IP, there is usually a very good reason for it. Unfortunately there's just nothing we can do about that. I can't investigate your IP if you never reached our servers - nothing would have been logged. – animuson May 31 at 16:06
  • OK. Got it. I know there is a good reason. This provider is very popular among spammers and other abusers exactly for the reason there is a lot of addresses and it is easy to change them. But if they block all of them, I'll be unable to connect when I am using mobile. – Pilot6 May 31 at 16:08
  • Is there any way to lift an IP ban? – user799558 Jun 23 at 22:18

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