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INT1
Explorer
Nov 13, 2024 8:39 AM UTC
Question

No response from peer error

When i try to connect to vpn through IPSEC IKv2 on specific devices its giving me no response from peer. i tried everything and even opened the specific ports on the firewall and router thought maybe it could block the connection and still the same issue.

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6 replies

pminarik
Staff
Staff
Nov 13, 2024 9:55 AM UTC

Check ike debug on the receiving end (FGT):

 

> diag vpn ike log filter clear
> diag vpn ike log filter dst-addr4 <public IP of your client>

> diag debug app ike 63

> diag debug enable

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INT1
INT1Author
Explorer
Dec 4, 2024 2:30 PM UTC

didnt help ipsec has alot of problems everyday im getting a new issue and its not easy to solve 

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pminarik
Staff
Staff
Dec 4, 2024 3:58 PM UTC

Those commands aren't supposed to help, they're supposed to generate outputs, which can then be analyzed to guide towards resolution or further analysis.

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dingjerry_FTNT
Staff
Staff
Dec 4, 2024 3:38 PM UTC

Hi @INT1 ,

 

It seems that the client is using FCT to connect to the IPSec VPN, which must be a dial-up VPN.

You mentioned "even opened the specific ports on the firewall and router":  What specific ports are they?

 

Anyway, please make sure that port 4500 is open on the upstream router.

 

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INT1
INT1Author
Explorer
Dec 5, 2024 12:00 PM UTC

hello, the specific ports are 500 and 4500 on both the firewall and the router's firewall and still having an issue.

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sjoshi
Staff
Staff
Dec 4, 2024 4:40 PM UTC

Hi @INT1 ,

 

Please run the pcap and verify the traffic from one end is reaching the other end

diag sniff packet any 'host x.x.x.x and (port 500 or port 4500)' 4 0 l >> where x.x.x.x is the remote peer IP

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Thanks, Salon
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