No Reply From DNS Server Alarm
acNoReplyFromDNSServerAlarm
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Alarm |
acNoReplyFromDNSServerAlarm |
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OID |
1.3.6.1.4.1.5003.9.10.1.21.2.0.155 |
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Description |
The alarm is sent when the device queries a DNS server and no reply is received. DNS queries are done for Proxy Sets that are configured with FQDNs. The alarm indicates the IP Interface (configured in the IP Interfaces table) on which the query was sent. The device periodically (configured by [ProxyIPListRefreshTime]) queries the DNS server to resolve FQDNs, which refreshes the Proxy Set’s list of DNS-resolved IP addresses. The device caches (stores) the last successful DNS resolution and if the DNS server subsequently goes offline when the device needs to do a DNS refresh query, instead of taking the Proxy Set offline, the device reuses the cached DNS-resolved addresses. In this scenario, the device continues sending DNS queries every 10 seconds. The device clears every entry in the cache 30 minutes after its time-to-live (TTL) value expires. However, if the DNS server is still offline and the device has deleted the cache, the device takes the Proxy Set offline. |
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Default Severity |
Minor |
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Source Varbind Text |
Board#1/ipInterface#<IP Interface Index> |
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Event Type |
communicationsAlarm |
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Probable Cause |
communicationsSubsystemFailure |
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Severity |
Condition |
Text |
Corrective Action |
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Minor |
No response from DNS server. |
"DNS server not responsive" |
Make sure that the configured IP address of the DNS server is correct. |
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Cleared |
Response received from DNS server. |
- |
- |