I can't find it in the cli:
Is there a way to get the srx to respond to ICMP packets whether the physical interface is up or down.
I know you can achieve this on an CISCO device, but I can't find a solution on srx devices.
The background is, that I want to monitor a VPN tunnel and there is only one PC connected directly to the srx.
Sometimes the PC is powered off and the link state goes down and it seems to me that the VPN tunnel went down.
You can't do that.
As a workaround you can assign one of the unused LAN IP with 32 bit netmask (/32) to lo0.0 interface and ping it instead of physical interface address.
In additionto what wdudys said, you would need to be doing some external logging such as to a syslog/snmp server and then have those send you an alert. You could also use an event srcipt to trigger an alert action.
That did the trick.
But since I use an IP address from the subnet I'm using on my vlan.0, I had to configure proxy-arp on vlan.0
set interfaces vlan unit 0 proxy-arp
Thanks for your help!!