{"draft":"draft-ietf-idr-long-lived-gr-06","doc_id":"RFC9494","title":"Long-Lived Graceful Restart for BGP","authors":["J. Uttaro","E. Chen","B. Decraene","J. Scudder"],"format":["HTML","TEXT","PDF","XML"],"page_count":"20","pub_status":"PROPOSED STANDARD","status":"PROPOSED STANDARD","source":"Inter-Domain Routing","abstract":"This document introduces a BGP capability called the \"Long-Lived\r\nGraceful Restart Capability\" (or \"LLGR Capability\").  The benefit of\r\nthis capability is that stale routes can be retained for a longer\r\ntime upon session failure than is provided for by BGP Graceful\r\nRestart (as described in RFC 4724). A well-known BGP community called\r\n\"LLGR_STALE\" is introduced for marking stale routes retained for a\r\nlonger time. A second well-known BGP community called \"NO_LLGR\" is\r\nintroduced for marking routes for which these procedures should not\r\nbe applied. We also specify that such long-lived stale routes be\r\ntreated as the least preferred and that their advertisements be\r\nlimited to BGP speakers that have advertised the capability. Use of\r\nthis extension is not advisable in all cases, and we provide\r\nguidelines to help determine if it is. \r\n\r\nThis memo updates RFC 6368 by specifying that the LLGR_STALE\r\ncommunity must be propagated into, or out of, the path attributes\r\nexchanged between the Provider Edge (PE) and Customer Edge (CE)\r\nrouters.","pub_date":"November 2023","keywords":[],"obsoletes":[],"obsoleted_by":[],"updates":["RFC6368"],"updated_by":[],"see_also":[],"doi":"10.17487\/RFC9494","errata_url":null}