When using the proxies for scraping or any other purpose, the main problem facing will be with the proxies being blocked.
Most common way of getting blocked are:
Same types of queries coming at a time
Same type of queries coming from not relevant geo-locations
Same type of queries from same user-agent type
Below are some techniques you can use to prevent blockage of your proxy.
Rotate the IP Address
When you are using the proxy for scraping or data harvesting, make sure not to make too many requests from a single proxy. Just keep on rotating the proxies every now and then so that the website doesn’t think of any suspicious activities.
Reduce Scraping Speed
Don’t push the website too much. Bots are designed to fetch data from the website much faster than humans. So slow down the scraping or data fetching. Also, if same kind of data is scraped through the same user agent, there are chances of getting multiple proxies blocked.
Respect the website
It is always good to go through the website’s crawling policy before scraping. Most of the websites have robots.txt on the root of their which provides info on that.
Use Mulitple User agents
As mentioned previously, using the same user-agent and scraping the same data increase the risks of detecting the proxies. So use multiple user-agents whenever possible. It is better to go with each user agent per IP.
Change Scrapping Patterns Occasionally
It is better to change the crawling patterns occasionally just to make the website think that the request is not from a bot.