> Source: [sk122993](https://support.checkpoint.com/results/sk/sk122993)

# sk122993 - Interface does not receive DHCP IP address if the interface is unplugged between machine shutdown and machine boot

| Property | Value |
|----------|-------|
| Solution ID | sk122993 |
| Date Created | 2018-02-16 |
| Last Modified | 2018-02-19 |
| Technical Level | Advanced |
| Products | Security Gateway, Security Management Server |
| Versions | R82.10, R82, R81.20, R82.20 |
| OS | Gaia |

## Symptoms

- * Interface does not receive DHCP IP address if the interface is unplugged between machine shutdown and machine boot.
* Running `ifconfig eth# up` after the machine boots causes the interface to receive a DHCP IP after a short period of time.
* Running `dhclient -r` before shutting down the machine causes the interface to be present and receive a DHCP IP correctly upon boot.

## Cause

When the*dhclient* function brings down an interface - due to the interface not having link, it runs *'ifconfig eth# down*'.

This brings the interface down at the OS level. However, the *dhclient* function never returns the interface to up state when it detects the cable is plugged back in.

As such, the interface will not return to normal state until a manual '*ifconfig eth# up*' is ran on the machine.

## Solution

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

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