Randomized IP Addresses: Distributed Crawling Systems

How important is it to change IPs randomly? First look at why crawlers are always blocked

Crawler's friend's biggest headache is the target site suddenly blocked IP. I have a friend to do e-commerce price comparison, just last week a platform blocked more than a dozen IP, so angry that he almost smashed the keyboard. In fact, this is to put it bluntly isVisiting behavior is too regular-Fixed IP + fixed time + fixed operation, the site does not seal you seal who?

To give a real example: a travel platform with machine fingerprinting detection, the same IP request more than 500 times in 3 hours directly pull black. At this time, if you canChange IP every 20 requests, in conjunction with random click intervals, the survival rate can be increased by more than 6 times.

How distributed crawlers play with IP randomization

Stand-alone crawlers change their IP's and are easily exposed.distributed systemThat's the way to go. Here's a real-world configuration plan:

 Python Example - Random Proxy IP Selection
import random
from scrapy.downloadermiddlewares.retry import RetryMiddleware

class RandomProxyMiddleware.
    def __init__(self, proxy_list).
        self.proxies = proxy_list This accesses the ipipgo API to get the latest IP pool.

    def process_request(self, request, spider): self.request.meta['proxy']: self.proxies = proxy_list
        request.meta['proxy'] = random.choice(self.proxies)
         Remember to set the timeout retry mechanism

There are just three key points:The IP pool has to be big enough(500+ dynamic IPs recommended),Switching frequency should be randomized(Don't fix every 10 changes),Geographical distribution should be wide. Previously tested with ipipgo's Dynamic Residential Proxy, the survival cycle is 3x longer than regular server room IPs.

How to choose a proxy IP without stepping into a pit?

There are all kinds of agency services in the market, teach you aThe Four Look Principles::

Highlight.Dynamic Residential IP, professional service providers like ipipgo are able to doChange IP for every request, also supports customized geography by business. Last time, there was a customer doing local life services, specifically to a third-tier city's residential IP, data collection efficiency directly doubled.

A practical guide to avoiding the pit (blood and tears experience)

1. Don't be fooled by the high stash of agents.Some of them are labeled as high stash actually http header will be leaked, remember to use online detection tool to measure the

2. IP pool to be dynamically updated: It is recommended to update the IP of 20% every hour to prevent being tagged by websites

3. Failure to Retry Be Smart: Don't change IP immediately when you encounter 403, hibernate for a random period of time and try again.

4. Traffic costs to be calculated: For volume-based billing like ipipgo, remember to set a daily usage limit!

Frequently Asked Questions QA

Q: What should I do if my proxy IP is slow?
A: Priority ElectionGeographically Nearest NodeIf you are a multinational collector, it is recommended to use their overseas acceleration line.

Q: How can I solve the problem of always encountering CAPTCHA?
A: Three steps: 1) Reduce request frequency 2) Change User-Agent 3) Switch high-reputation IPs (ipipgo's Enterprise package has a dedicated channel)

Q: Build my own proxy pool or buy a service?
A: Unless the tech team is too good, you can just buy off-the-shelf. The cost of maintaining your own IP pool (server + blocking loss) is 3-5 times higher than buying a service.

Finally, an industry secret: many websites now use theIP Reputation Scoring SystemThe reason why ipipgo's dynamic pool is stable is that their IPs come from real home broadband, and each IP is not used more than five times before it is automatically replaced, and this program does have a set of anti-climbing.