I am currently having problems with AIX and network performance.
I have an AIX 7.2 on-premises and a Linux with RH 7.7 Maipo in Google Cloud. Between the 2 machines I have a guaranteed bandwith of 1 Gbit/s.
Firstly I started with a trivial traceroute: what I noticed is that after some hops appears the following error "fragmentation required, trying new MTU=1492". Basically this appears 4 times: MTU changes from the starting 1500 to 1492, then to 1480, then to 1472 and finally to 1006. This brings also a very very low throughput (around 16 Mbit/s). Do you have any idea of what's going on? If I try the same experiment from a Linux machine I don't get this issue and the throughtput is quite good (around 320 Mbit/sec).
thank you 