networking routing ai_generated partial

OSPF: LSDB overload detected, max LSA limit (10000) reached on area 0.0.0.0, dropping new LSAs

ID: networking/ospf-lsdb-overload

Also available as: JSON · Markdown · 中文
88%Fix Rate
86%Confidence
1Evidence
2024-06-12First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
Cisco IOS 15.9(3)M active — — —
Juniper Junos 22.2R2 active — — —
FRRouting 8.4 active — — —

Root Cause

The OSPF Link State Database (LSDB) has exceeded the configured maximum number of Link State Advertisements (LSAs) due to route flapping or a misconfigured router injecting excessive routes, causing the router to drop new LSAs and potentially corrupt the routing table.

generic

中文

由于路由震荡或错误配置的路由器注入过多路由，OSPF链路状态数据库（LSDB）超过配置的最大链路状态通告（LSA）数量，导致路由器丢弃新的LSA并可能损坏路由表。

Official Documentation

https://www.cisco.com/c/en/us/support/docs/ip/open-shortest-path-first-ospf/7039-1.html

Workarounds

  1. 90% success Identify the source of excessive LSAs using 'show ip ospf database' and 'show ip route ospf' to find flapping routes, then configure route summarization or set a route filter to limit the number of redistributed routes. 
    Identify the source of excessive LSAs using 'show ip ospf database' and 'show ip route ospf' to find flapping routes, then configure route summarization or set a route filter to limit the number of redistributed routes.
  2. 85% success Configure OSPF stub area or totally stubby area on the affected area to reduce LSA flooding: area 0.0.0.0 stub no-summary 
    Configure OSPF stub area or totally stubby area on the affected area to reduce LSA flooding: area 0.0.0.0 stub no-summary
  3. 75% success Temporarily increase the max LSA limit to 15000 while investigating: router ospf 1; max-lsa 15000; then set a timer to revert after 24 hours. 
    Temporarily increase the max LSA limit to 15000 while investigating: router ospf 1; max-lsa 15000; then set a timer to revert after 24 hours.

中文步骤

  1. Identify the source of excessive LSAs using 'show ip ospf database' and 'show ip route ospf' to find flapping routes, then configure route summarization or set a route filter to limit the number of redistributed routes.
  2. Configure OSPF stub area or totally stubby area on the affected area to reduce LSA flooding: area 0.0.0.0 stub no-summary
  3. Temporarily increase the max LSA limit to 15000 while investigating: router ospf 1; max-lsa 15000; then set a timer to revert after 24 hours.

Dead Ends

Common approaches that don't work:

  1. 80% fail

    This only masks the problem; if the LSA flood is due to a misconfiguration or attack, the LSDB will eventually exceed the new limit and cause memory exhaustion.

  2. 85% fail

    The LSDB will be rebuilt from neighbors after reboot; if the underlying issue (e.g., route flapping) is not fixed, the overload will recur quickly.

  3. 90% fail

    This causes a complete network outage and does not address the LSA source; the overload will return once OSPF is re-enabled.