General slowness or high latency is observed when connecting to AWS Console through ProxySG.
Packet capture taken on ProxySG shows that AWS Console(Destination) is advertising small TCP Window sizes:
It's due to the fact that ProxySG is not configured to use TCP Windows Scaling(RFC1323).
To enable Windows Scaling on ProxySG:
ProxySG>enable
Enable Password:
ProxySG#config t
Enter configuration commands, one per line. End with CTRL-Z.
ProxySG#(config)show tcp-ip
RFC-1323 support: enabled
TCP Newreno support: enabled
IP forwarding: enabled
ICMP bcast echo response: disabled
ICMP timestamp echo response: disabled
Path MTU Discovery: disabled
TCP silly-window avoidance: enabled
Routing algorithm: weighted-round-robin
TCP 2MSL timeout: 120 seconds
TCP window size: 2031585 bytes
TCP Loss Recovery Mode: normal
Bypass connection keep-alive: disabled
Fast retransmit: enabled
Fast TCP FIN_WAIT_2 recycle: disabled
SCPS link bandwidth: (not configured)
SCPS interface: (not configured)
SCPS link rtt: (not configured)
SCPS processing: Disabled