Since yesterday I have not been able to access the Lasair website or query objects. When doing the latter I get a ConnectionError with the message “HTTPSConnection(host=‘api.lasair.lsst.ac.uk’, port=443): Failed to establish a new connection: [Errno 61] Connection refused”. In the morning I was briefly able to access the website and query a few objects but it quickly failed again.
Others at my institute can also not connect. The Lasair Status page says that the LSST website is up but the link connects to the ZTF website.
Is this a known issue or could this be a problem from my end?
The Lasair (ZTF and LSST) web servers employ rate limiters to protect us against the rising tide of crawler bots. Unfortunately, they sometimes mistakenly catch real users and lock them out for a set period. This is what was happening to Erin and friends.
After investigation, we have adjusted our non-API rate limits. As a general rule, when hitting a non-API Lasair URL (e.g., object pages or fits stamp links), don’t exceed 1 request / second, and you should be ok.