Discovery : TCP connection dropped error

[Meenakshi Rajes]

Hi All,

I have tried the discovery for few of the servers but it's showing the error - Cannot connect, status is TCP_CONNECTION_DROPPED. Connection unexpectedly closed by SSH server in PROD instance.

When I try to discovery the same server in DEV instance, it's updating the CI.

Can anyone please let me know why this is happening or how to trouble shoot it?

[Manuel Stimac]

Hi @Meenakshi Rajes,

I would try the following first:

1. Network access (Firewalls open to discover the systems?)
2. Review Credentials & test them
3. Update Discovery/Service Mapping Patterns
4. Check Agent.log & Wrapper.log from the MID Server at time of Discovery
5. Debug the Pattern itself

Some of those checks are quite simple - I know - but I experienced really strange behaviors and at the end it was either some blocked traffic or wrong User/PWD. Hope this helps.

If this answer helps you please mark it as Helpful/Solution.
Thanks & Regards - Manuel 

[Manuel Stimac]

Hi @Meenakshi Rajes,

do you need any more help with this? If my answer helped you, please mark it as Helpful/Solution so other will find it too.

Thanks & many regards - Manuel 

[Vini]

Hi @Meenakshi Rajes , @Manuel Stimac ,

We also have the same issue and we got resolved.

Discovery Error#

Cannot connect, status is TCP_CONNECTION_DROPPED. Connection unexpectedly closed by SSH server

Error Captured on the Server when trigger Discovery#

pam_unix(sshd:account): account <Account Name>  has expired (account expired)

Apr 18 2023 10:12:04 <<Server name>> sshd[12575]:fatal: Access denied for user <<cnf_mgmt>> by PAM account configuration [preauth]

Resolution: 

Executed following Command on the Target server#

chage -m 0 -M 99999 -I -1 -E -1 <<Account Name>

Note# above is to make sure the discovery account never expire again. then we are able to discover the server

Hope this Help, if so please mark it to Helpl & Solved

[Vini]

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