shorter lease times after dhclient update

Issues related to configuring your network
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Re: shorter lease times after dhclient update

Post by TrevorH » 2018/05/20 12:34:01

The running dhclient does use -cf and points to /var/lib/NetworkManager/dhclient-wlp1s0.conf
# Created by NetworkManager

send host-name "xps13"; # added by NetworkManager

option rfc3442-classless-static-routes code 121 = array of unsigned integer 8;
option ms-classless-static-routes code 249 = array of unsigned integer 8;
option wpad code 252 = string;

also request rfc3442-classless-static-routes;
also request ms-classless-static-routes;
also request static-routes;
also request wpad;
also request ntp-servers;
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Re: shorter lease times after dhclient update

Post by pjsr2 » 2018/05/20 21:35:21

dhcp-lease-time in dhcp.conf specifies the lease time requested by the client. The dhcp server may return a smaller value than this requested value. This may happen if the max-lease-time specified in the dhcp server configuration has a smaller value.

When the number of leases handed out by the dhcp server is approaching the maximum number of leases, the dhcp server will start to reduce the lease time in order to avoid exhausting the pool of available leases.

Check the number of leases in use on the dhcp server(s) and verify that sufficient free leases are available.

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Re: shorter lease times after dhclient update

Post by drknut » 2018/06/01 06:03:16

Finally I must conclude, unfortunately without any proof, that a change occurred on the server the same day as the client update.

Maybe an exhaust of free leases as pjsr2 suggested.

I tested with a W10 client, leases are also limited to 3600 seconds.

I am reluctant to mark this topic as [SOLVED], since there is finally no problem.

@Trevor : feel free to tag/change the subject as you deem appropriate.

@All : thank you for your help.

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