Can't increment stick table if silently dropping

Help!
1

My goal is to temporarily block an IP if someone tries to access certain paths. The idea is to use a stick table with gpc0, and when a forbidden path is accessed, gpc0 is increased by 1. That’s then used as an indicator for later attempts that the IP is banned.

Here’s my config for the frontend:

frontend nameoffrontend
    # ban for 20 minutes
    stick-table type ip size 100k expire 20m store gpc0
    
    # flag client as either getting blocked or already being blocked
    acl    getblocked   path -m reg -i regex-for-some-forbidden-path
    acl    isblocked    sc_get_gpc0(0,nameoffrontend) gt 0
    
    http-request   track-sc0 src
    # increase gpc0 if getting blocked
    http-response  sc-inc-gpc0(0)  if    getblocked
    # in either case, silently drop the connection
    http-request   silent-drop     if    getblocked or isblocked

The silently dropping works fine when accessing a forbidden path, but gpc0 never gets increased and the ban never happens. The client can immediately continue accessing other things on the server. If I change the last line to
http-request deny if getblocked or isblocked
it works as expected. A forbidden path leads to a 403, gpc0 gets increased, and subsequent attemts at any valid path also leads to a 403. I just want to change that 403 to silence.

2

sc-inc-gpc0 action is used with http-response, with means it will not be evaluated when http-request silent-drop is executed, because no response will happen.

You may want to execute the sc-inc-gpc0 action on http-request as well:

    http-request   track-sc0 src
    # increase gpc0 if getting blocked
    http-request  sc-inc-gpc0(0)  if    getblocked
    # in either case, silently drop the connection
    http-request   silent-drop     if    getblocked or isblocked