Interactsh is not always triggered when scanning large lists

[reacan]

Hello everyone,

I am scanning URL lists with "nuclei -l list.txt -iserver my.interactsh.srv -itoken thetoken" and I noticed that the message "[INF] Using Interactsh Server: my.interactsh.srv" doesn't always appear, checked the access logs on my server and really there are scans that do not trigger Interactsh.

Tried to find the threshold, at first seemed like it is around 55 URLs, then again it came down to about 30 URLs. Inconsistent.

When scanning single URLs the Interactsh server is always triggered.

Tried adding the flags "for the most thorough scan" -severity info,low,medium,high,critical -rl 150 -bs 50 -c 50 -timeout 10 -retries 3, still the same result:

[INF] Found 29 URL from httpx
[INF] Templates clustered: 2275 (Reduced 79402 Requests)
[INF] Using Interactsh Server: my.interactsh.srv

[INF] Running httpx on input host
[INF] Found 67 URL from httpx
[INF] Templates clustered: 2275 (Reduced 197432 Requests)
And no Interactsh here :(

Does anyone know anything about this? How do you scan massive lists and make sure that the scan is thorough with Interactsh being used?

Many thanks in advance for your insights!