From 46b8abe7e6ca84c2d0efb980e1814d34a17b9310 Mon Sep 17 00:00:00 2001 From: Chirag Shah Date: Thu, 25 Apr 2024 18:52:31 -0700 Subject: [PATCH] tools: Handle seq num for BGP as-path in frr-reload.py If frr.conf has bgp as-path access-list clause without sequence number then upon performing frr-rleoad, the running config clause with sequence number will always be deleted and the new ones without sequence will be re-added. This could lead to blackholing until the config gets reapplied. Testing: frr.conf: bgp as-path access-list important_internet_bgp_as_numbers permit _16509_ Running config: bgp as-path access-list important_internet_bgp_as_numbers seq 5 permit _16509_ ! Before fix Upon frr-reload it deletes and readd line as without seq 2024-04-26 03:16:45,772 INFO: Executed "no bgp as-path access-list important_internet_bgp_as_numbers seq 5 permit _16509_" 'bgp as-path access-list important_internet_bgp_as_numbers permit _16509_\n' After fix: no form is not executed and no delta determine between frr.conf and running-config. Signed-off-by: Chirag Shah (cherry picked from commit 439c6f70b5bf7c8d92719458a37c9cce70b241c9) --- tools/frr-reload.py | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/tools/frr-reload.py b/tools/frr-reload.py index 9c20d0099f..b06f1df624 100755 --- a/tools/frr-reload.py +++ b/tools/frr-reload.py @@ -1459,6 +1459,35 @@ def ignore_delete_re_add_lines(lines_to_add, lines_to_del): lines_to_add.append((add_cmd, None)) lines_to_del_to_del.append((ctx_keys, None)) + # bgp as-path access-list can be specified without a seq number. + # However, the running config always + # adds `seq X` (sequence number). So, ignore such lines as well. + # Examples: + # bgp as-path access-list important_internet_bgp_as_numbers seq 30 permit _40841_" + re_bgp_as_path = re.search( + "^(bgp )(as-path )(access-list )(\S+\s+)(seq \d+\s+)(permit|deny)(.*)$", + ctx_keys[0], + ) + if re_bgp_as_path: + found = False + tmpline = ( + re_bgp_as_path.group(1) + + re_bgp_as_path.group(2) + + re_bgp_as_path.group(3) + + re_bgp_as_path.group(4) + + re_bgp_as_path.group(6) + + re_bgp_as_path.group(7) + ) + for ctx in lines_to_add: + if ctx[0][0] == tmpline: + lines_to_del_to_del.append((ctx_keys, None)) + lines_to_add_to_del.append(((tmpline,), None)) + found = True + if found is False: + add_cmd = ("no " + ctx_keys[0],) + lines_to_add.append((add_cmd, None)) + lines_to_del_to_del.append((ctx_keys, None)) + if ( len(ctx_keys) == 3 and ctx_keys[0].startswith("router bgp")