tools: improve frr-reload delete performance for some commands

Problem seen when deleting many static routes or access-lists due
to frr-reload.py issuing individual vtysh -c commands for every
line. On slow switches, this can take long enough for systemd to
time out the reload process and restart frr.  This fix uses add
logic for static routes, prefix-lists, and access-lists to gang
the changes together.

Signed-off-by: Don Slice <dslice@cumulusnetworks.com>
Ticket: CM-27856

diff --git a/tools/frr-reload.py b/tools/frr-reload.py
index 3e97635dfe0d5754f933e3562134bd147f460962..45843faf1363a3aca281a3b1aea8edb89d666ba2 100755 (executable)
--- a/tools/frr-reload.py
+++ b/tools/frr-reload.py
@@ -934,6 +934,16 @@ def ignore_delete_re_add_lines(lines_to_add, lines_to_del):
                     lines_to_del_to_del.append((ctx_keys, route_target_export_line))
                     lines_to_add_to_del.append((ctx_keys, route_target_both_line))
 
+        # Deleting static routes under a vrf can lead to time-outs if each is sent
+        # as separate vtysh -c commands. Change them from being in lines_to_del and
+        # put the "no" form in lines_to_add
+        if ctx_keys[0].startswith('vrf ') and line:
+            if (line.startswith('ip route') or
+                line.startswith('ipv6 route')):
+                add_cmd = ('no ' + line)
+                lines_to_add.append((ctx_keys, add_cmd))
+                lines_to_del_to_del.append((ctx_keys, line))
+
         if not deleted:
             found_add_line = line_exist(lines_to_add, ctx_keys, line)
 
@@ -1054,6 +1064,19 @@ def compare_context_objects(newconf, running):
                 for line in running_ctx.lines:
                     lines_to_del.append((running_ctx_keys, line))
 
+            # Some commands can happen at higher counts that make
+            # doing vtysh -c inefficient (and can time out.)  For
+            # these commands, instead of adding them to lines_to_del,
+            # add the "no " version to lines_to_add.
+            elif (running_ctx_keys[0].startswith('ip route') or
+                  running_ctx_keys[0].startswith('ipv6 route') or
+                  running_ctx_keys[0].startswith('access-list') or
+                  running_ctx_keys[0].startswith('ipv6 access-list') or
+                  running_ctx_keys[0].startswith('ip prefix-list') or
+                  running_ctx_keys[0].startswith('ipv6 prefix-list')):
+                add_cmd = ('no ' + running_ctx_keys[0],)
+                lines_to_add.append((add_cmd, None))
+
             # Non-global context
             elif running_ctx_keys and not any("address-family" in key for key in running_ctx_keys):
                 lines_to_del.append((running_ctx_keys, None))
@@ -1392,6 +1415,11 @@ if __name__ == '__main__':
                     if line == '!':
                         continue
 
+                    # Don't run "no" commands twice since they can error
+                    # out the second time due to first deletion
+                    if x == 1 and ctx_keys[0].startswith('no '):
+                        continue
+
                     cmd = line_for_vtysh_file(ctx_keys, line, False)
                     lines_to_configure.append(cmd)