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Datacenter Network Troubleshooting
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Datacenter Network Troubleshooting

HardSQL · PostgreSQL

Problem

Troubleshoot a spine-and-leaf datacenter network scenario involving servers and firewalls. Using the supplied network observations, identify servers with a missing, unknown, or non-operational leaf link, or with a denied required flow. Treat the highest-priority enabled matching firewall rule as authoritative; if no rule matches, treat the flow as denied.

Output

  1. One row per affected server with hostname, leaf_device, link_status, blocked_flows, and diagnosis.
  2. Include only affected servers, ordered by incident severity descending, then hostname ascending.

Schema

servers
ColumnTypeDescription
server_idPKINTServer identifier
hostnameVARCHAR(100)Server hostname
zoneVARCHAR(50)Firewall source zone
required_serviceVARCHAR(50)Required service name
required_portINTRequired destination port
network_devices
ColumnTypeDescription
device_idPKINTNetwork device identifier
device_nameVARCHAR(100)Device name
device_roleVARCHAR(30)Spine, leaf, or firewall role
server_links
ColumnTypeDescription
link_idPKINTLink observation identifier
server_idINTReferenced server
leaf_idINTReferenced leaf device
link_statusVARCHAR(20)Observed link status
observed_atTIMESTAMPObservation timestamp
firewall_rules
ColumnTypeDescription
rule_idPKINTFirewall rule identifier
source_zoneVARCHAR(50)Source security zone
destination_zoneVARCHAR(50)Destination security zone
destination_portINTDestination port
actionVARCHAR(10)Allow or deny action
priorityINTRule precedence
enabledBOOLEANWhether the rule is active
flow_logs
ColumnTypeDescription
flow_idPKINTFlow observation identifier
server_idINTOriginating server
destination_zoneVARCHAR(50)Destination security zone
destination_portINTDestination port
observed_atTIMESTAMPFlow observation timestamp
Tablesserversnetwork_devicesserver_linksfirewall_rulesflow_logs
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