I have two DNS servers connectted to Cisco7513 router,recently,I found that there are lots of packet ssourced from diffrent IP address destinated to DNS server. The CPU utilization of 7513 was very high(up to 95%).
There are two output FE port in this router,I closed one port,the CPU utilization down.
I don't know why this happened.I think maybe the DNS servers were attacked .
Can you tell me a method to avoid this issue?
Should I do some change on the configuration of the router?
If you are very worried about your network security, I would suggest that you go for an IDS, which will detect and warn you if any attacks takes place. Based on the alarms you can take immediate actions.
Table of ContentsIntroductionVersion HistoryPossible Future
UpdatesDocuments PurposeNAT Operation in ASA 8.3+ SectionsRule Types
Network Object NATTwice NAT / Manual NATRule Types used per SectionNAT
Types used with Twice NAT / Manual NAT and Network Obje...
Table of Contents Introduction:This document describes details on how
NAT-T works. Background: ESP encrypts all critical information,
encapsulating the entire inner TCP/UDP datagram within an ESP header.
ESP is an IP protocol in the same sense that TCP an...