ocket8888 commented on a change in pull request #3140: Add traffic_ops_ort.pl suuport for processing ##OVERRIDE## lines from… URL: https://github.com/apache/trafficcontrol/pull/3140#discussion_r246026009
########## File path: docs/source/admin/traffic_ops/using.rst ########## @@ -541,6 +542,50 @@ The deliveryservice screen also allows you to set the DSCP value of traffic sent .. Note:: The DSCP setting in the UI is *only* for setting traffic towards the client, and gets applied *after* the initial TCP handshake is complete, and the HTTP request is received (before that the cache can't determine what deliveryservice this request is for, and what DSCP to apply), so the DSCP feature can not be used for security settings - the TCP SYN-ACK is not going to be DSCP marked. +.. index:: + Raw Remap Text + +.. _raw-remap-text: + +ANY_MAP Raw Remap Text +---------------------- +The Raw Remap Text may contain the following special strings that will be replaced by traffic_ops_ort.pl at the edge and mid levels: + ++---------------------+--------------------------------------+ +| Traffic Ops Entry | Gets Replaced with | ++=====================+======================================+ +| __CACHE_IPV4__ | The cache's IPv4 address | ++---------------------+--------------------------------------+ +| __HOSTNAME__ | Short hostname (same as hostname -s) | ++---------------------+--------------------------------------+ +| __FULL_HOSTNAME__ | Long hostname (same as hostname) | ++---------------------+--------------------------------------+ +| __SERVER_TCP_PORT__ | Server TCP incoming port number | ++---------------------+--------------------------------------+ +| __RETURN__ | A newline | ++---------------------+--------------------------------------+ + +The ##OVERRIDE## special string was added to allow an ANY_MAP rule to override another Delivery Service's remap rule, implemented inside traffic_ops_ort.pl. The original remap rule is commented out with an ##OVERRIDDEN## prefix and the ##OVERRIDE## rule is activated in its place. + +.. Note:: The from endpoint must exactly match for this to properly work (ie: trailing url '/'), otherwise ATS may fail to initialize or reload while processing remap.config. + +For example given remap rule: :: + + map http://from.com/ http://to.com/ + +And raw remap text override: :: + + ##OVERRIDE## map http://from.com/ http://to.com/ thundering_herd_mitigation.so + +Results in remap.config lines as: :: + + ##OVERRIDE## + map http://from.com/ http://to.com/ thundering_herd_mitigation.so + ##OVERRIDDEN## map http://from.com/ http://to.com/ + +The ANY_MAP ##OVERRIDE## may be used to incrementally deploy plugins by assigning a subset of caches to the ANY_MAP ##OVERRIDE## Delivery Service in addition to the original Delivery Service. This allows Traffic Router to send traffic to edges based on the original Delivery Service but serve them using the ANY_MAP override Raw Remap Text. + +.. Note:: The ANY_MAP ##OVERRIDE## special string is a temporary solution and will be deprecated when Deliver Service Versioning is implemented. Review comment: Just a suggestion, this could link to an email thread/GitHub Issue/Pull Request. Or any combination thereof. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services
