A GRE tunnel is configured between Router1 and Router2 across the Internet. Performance on
the GRE tunnel is slow and Router1 is receiving ICMP messages from Router2.
What is the cause of this problem?
A.
The do-not-fragment (DF) bit has not been set on Router2.
B.
The do-not-fragment (DF) bit has not been set on Router1.
C.
There is a duplex setting mismatch on the GRE tunnel.
D.
The maximum segment size (MSS) setting has not been configured correctly for the GRE
tunnel.