> Source: [sk121120](https://support.checkpoint.com/results/sk/sk121120)

# sk121120 - Cannot establish SIC with fresh installed Secondary MDS/MLM server

| Property | Value |
|----------|-------|
| Solution ID | sk121120 |
| Date Created | 2017-10-30 |
| Last Modified | 2023-03-05 |
| Technical Level | Advanced |
| Products | Multi-Domain Security Management Server |
| Versions | R81.10 (EOS) |
| OS | Gaia |
| Platform | Smart-1 |

## Symptoms

- * "`Error: Certificate cannot be pushed`" when establishing SIC with a new MDS/MLM server from SmartConsole.
* The "`netstat -nap | grep 18211`" command on the new MDS/MLM server shows that it is actually listening for packets on port 18211 which is used for pushing certificates from the ICA to the MDS/MLM server.
* The default management interface for the new MDS/MLM was changed to a different interface other than the default 'Mgmt' interface
* "`SIC Status for MDS/MLM-NAME: Not Communicating`" and "`Peer does not have a certificate for SIC [error no. 111]`" during SIC initialization.

## Cause

* CPD process listens on port 18211 using an IP address different from the new configured Leading IP address for the MDS.
* MTU\> 1500 (Jumbo Frame) is configured on the management interface

## Solution

This solution requires authentication. Please log in to view the full solution.

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