Cisco Bug: CSCuo93772 - VPN Connection Fails with Error "MTU too small"
Jul 03, 2018
- Cisco AnyConnect Secure Mobility Client
Known Affected Releases
Symptom: When trying to connect from a machine with a physical interface MTU of 1366 or lower, AnyConnect sometimes fails with the error message "The client's MTU configuration sent from the secure gateway is too small. A value of at least 1280 is required in order to tunnel IPv6 traffic. Please contact your network administrator." Conditions: Seen using AnyConnect 3.1.05160 and ASA version 9.1(5), with physical interface MTU between 1357 and 1368.
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Bug Details Include
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