Hi Rushi,
SSH connection is from a Zone-A at SRX3400 to Zone-B at SRX240.
There is not packet loss in ping test either.
There is another symptom. Same thing happens when I try to make http request also.
My setup on both sides is;
set security ike proposal IKE-PROP-MN-DGN-1 lifetime-seconds 3600
set security ike proposal IKE-PROP-MN-DGN-1 authentication-method pre-shared-keys
set security ike proposal IKE-PROP-MN-DGN-1 authentication-algorithm sha1
set security ike proposal IKE-PROP-MN-DGN-1 encryption-algorithm aes-128-cbc
set security ike proposal IKE-PROP-MN-DGN-1 dh-group group5
set security ike policy IKE-POL-MN-DGN-1 proposals IKE-PROP-MN-DGN-1
set security ike policy IKE-POL-MN-DGN-1 mode main
set security ike policy IKE-POL-MN-DGN-1 pre-shared-key ascii-text {SOMEPASS}
set security ike gateway IKE-GW-MN-DGN-1 ike IKE-POL-MN-DGN-1
set security ike gateway IKE-GW-MN-DGN-1 address {IP}
set security ike gateway IKE-GW-MN-DGN-1 external-interface ge
set security zones security-zone untrust host-inbound-traffic system-services ike
set security ipsec proposal IPSEC-PROP-MN-DGN-1 lifetime-seconds 3600
set security ipsec proposal IPSEC-PROP-MN-DGN-1 protocol esp
set security ipsec proposal IPSEC-PROP-MN-DGN-1 authentication-algorithm hmac-sha1-96
set security ipsec proposal IPSEC-PROP-MN-DGN-1 encryption-algorithm aes-128-cbc
set security ipsec policy IPSEC-POL-MN-DGN-1 proposals IPSEC-PROP-MN-DGN-1
set security ipsec policy IPSEC-POL-MN-DGN-1 perfect-forward-secrecy keys group5
set security ipsec vpn IPSEC-VPN-MN-DGN-1 ike gateway IKE-GW-MN-DGN-1
set security ipsec vpn IPSEC-VPN-MN-DGN-1 ike ipsec-policy IPSEC-POL-MN-DGN-1
set security ipsec vpn IPSEC-VPN-MN-DGN-1 vpn-monitor
set security ipsec vpn IPSEC-VPN-MN-DGN-1 establish-tunnels immediately
set security ipsec vpn IPSEC-VPN-MN-DGN-1 bind-interface st0.1
set interfaces st0 unit 1 family inet
set security zone security-zone VPN-MN-DGN1 interfaces st0.1
set routing-options static route 10.9.0.0/22 next-hop
on security zone policy, any source to any destination with any application is permitted.
Thanks