Could not open outbound connection?
Last modified on 9 Mar, 2021. Revision 4
"Could not open outbound connection?" message when using the Ping CLI command
Up to date for | cOS Core 12.00.xx |
Supported since | cOS Core 8.x |
Status | OK |
Author | Peter Nilsson |
Question:
When i perform a ping from the CLI console i get the following message : “Could not open outbound connection?” What is the reason for this?
Answer:
There are many of reasons for this, below is a list of both common and uncommon reasons.
- Failed to find a route to the destination IP
- Failed to find a route to the source IP
- The connection table is full (and conn-replace fails)
- Failed to acquire a new ICMP ID or source TCP/UDP port for NAT'ing
- UDP Src Port 0 is specified, but not allowed (by setting)
- Failed to acquire an IP from the NAT pool
- SLB fails to apply the configured policy
- Threshold rules does not allow a new connection at this stage
The first two, “Failed to find a route to dest/src IP” is the most common causes of this message.
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