Update for dhcp and lag tests (#21499)

What is the motivation for this PR?
Update the loganalyzer ignore list to fix a regex issue, and update the GCU test to ignore new error syslogs.

The regex for ignoring systemd-networkd.socket failing to start included [1], which has a special meaning when interpreted as regex (match one character that has 1 in it; in other words, match a 1). Escape the brackets so that they get treated literally.

sonic-net/sonic-utilities#4105 started logging errors when a GCU command fails with a non-zero exit status. However, there is one case of a (known) failure where dhcp_relay fails to restart because it hit the start limit. These error logs need to be ignored.

Signed-off-by: Saikrishna Arcot <[email protected]>
Signed-off-by: selldinesh <[email protected]>

Author: saiarcot895

ansible/roles/test/files/tools/loganalyzer/loganalyzer_common_ignore.txt

@@ -424,7 +424,7 @@ r, ".*ERR pmon.*Failed to unfreeze VDM stats in contextmanager for port.*"
 r, ".*ERR bgp\#bgpmon:\s+\*ERROR\*\s+Failed\s+with\s+rc:\d+\s+when\s+execute:\s+.*vtysh.*-c.*show\s+bgp\s+summary\s+json.*"
 
 # Ignore systemd-networkd.socket not being able to be started. This is expected on non-DPU platforms.
-r, ".*ERR systemd[1]: Failed to listen on systemd-networkd.socket - Network Service Netlink Socket.*"
+r, ".*ERR systemd\[1\]: Failed to listen on systemd-networkd.socket - Network Service Netlink Socket.*"
 
 # Ignore syncd error when switching global packet trimming mode
 r, ".*ERR .* SAI_API_SWITCH:brcm_sai_switch_pkt_trim_qos_tc_egr_entries_create:.* Egress qos map with idx .* entries are already present.*"

tests/generic_config_updater/conftest.py

@@ -78,7 +78,14 @@ def ignore_expected_loganalyzer_exceptions(duthosts, selected_dut_hostname, loga
     if loganalyzer:
         ignoreRegex = [
             ".*ERR sonic_yang.*",
-            ".*ERR.*Failed to start dhcp_relay.service - dhcp_relay container.*",  # Valid test_dhcp_relay for Bookworm
+
+            # Valid test_dhcp_relay for Bookworm and newer
+            ".*ERR.*Failed to start dhcp_relay.service - dhcp_relay container.*",
+            ".*ERR GenericConfigUpdater:.*Command failed: 'nsenter --target 1"
+            ".*systemctl restart dhcp_relay', returncode: 1",
+            ".*ERR GenericConfigUpdater:.*stderr: Job for dhcp_relay.service "
+            "failed because start of the service was attempted too often.",
+
             ".*ERR.*Failed to start dhcp_relay container.*",  # Valid test_dhcp_relay
             # Valid test_dhcp_relay test_syslog
             ".*ERR GenericConfigUpdater: Service Validator: Service has been reset.*",