LaserJet Printing

Hi Everyone,

Found a fix for my HP LaserJet 400 printer (wired ethernet) repeatedly dropping offline every few hours, after establishing an IP address on the R7800 Nighthawk router.  Having dropped offline you could not print from any networked computer.  

All other standard Hewlett Packard printer connectivity troubleshooting techniques had been tried and this turned out to be the underlying issue after four days of diagnosis.

Problem Solution

Extend the DHCP & fixed IP address lease times from the standard 24 hours to 7 days (or longer).

There is no built-in GUI (Graphical User Interface) with Netgear routers to do this, much as it has been requested by other community members in the past, so you have to use Telnet backend to update the router settings.

All credit for this solution provided here goes to Andy & jlewter (thank you both so very much).  There are a lot of "Do so at your own risk" provisos given in the message thread that I advise you to read very carefully but on a small home or home office network with just a few devices connecting extending the time should not be a big issue.

Windows 10 by default has Telnet turned off so you have to enable it.  A good how to is shown here.

Excerpt from solution thread:

This is an extract from an archived thread, posted by ‘jlewter’ about five years ago. I’m not sure if the change is persistent through a 
router power cycle / reboot, and I’m not entirely sure if it can be applied to all routers (in the case below it was a WNDR3700).

"do at your own risk.

telnetenable
log into router
# cd bin
# config backup /tmp/configbackup.bin
(use a usb stick to copy it off)
# config set lan_lease=604800
(this is 7 days, 60*60*24*7 in seconds)
# config commit

Notes here.. 
*Tinkering with these values are done at your own risk.
*Rebooting will NOT reset this value.
*Editing the LAN / DHCP page in the router will NOT reset this value.
*If you have a lot of different devices coming on and going off then this could slow the router down.
*If you ever change your lease time DOWNWARDS then you need to reboot ALL devices on the network because the lease will EXPIRE on DHCP server and not the client.
*3 - 7 days is the ideal lease time. Setting it for a few mins will be deadly to the router ;P. Setting it for 3 years (nearly) will just be silly.
*Tinkering with these values are done at your own risk.

Side Notes here..
*Settings are exported as plain text (this might be useful for other things).. 
*If you dont know how to copy files from the prompt then the command is "cp" and the usb drives are usually mounted under mnt1 or mnt/mnt1 (not gonna check it's late)
*Dont try to enable local DNS caching by changing the values, I did, It still doesnt work..
*Tinkdering with these values are done at your own risk. "

Problem Definition

After power resetting, the HP LaserJet 400 M401dne (wired ethernet printer to router) would appear within the R7800 router Attached Devices table with a valid IP address, then after several hours (it varied) drop off the Attached Devices list. After dropping off the list you could no longer connect to the printer via the network, to wake it up and print, with the printer being reported as being offline.

At that point only a full power off (uplug/replug - 30 sec) reset would allow the printer to re-establish a new IP address with the router.

Bringing the printer out of sleep mode by pressing the printer power button, did nothing to re-establish a new IP address.  On the printer setup, the power off never setting was turned on, so the printer never fully powers itself off.  You can not turn the sleep mode option off with this model only select how long before it goes to sleep but it does have a wake on LAN feature.

Router Setup

As recommended in the HP Community forums the the printer was setup with a fixed IP address (printer control panel) and outside the DHCP LAN range setup on the router.  You can use whichever DHCP range you wish and whichever fixed IP address works for you, this is just my setup.

LAN Setup

LAN TCP/IP Setup

IP Address:  192.168.1.1

IP Subnet Mask:  255.255.255.0

Use Router as DHCP Server

Starting IP Address:  192.168.1.11

Ending IP Address:  192.168.1.254

Address Reservation

Printer IP Address:  192.168.1.10

Printer Device Name:  LASERJET400 (device name setup in printer control panel)

Printer MAC Address:  xxxxxxxxxxx (MAC address of the device)

In theory with a fixed IP address outside of the DHCP address range set on the printer itself (not within the router), you don't need to do the DHCP address reservation but it just made things clearer and reminded me on returning to the LAN Setup screen what was going on.  The address reservation doesn't cause a problem as 192.168.1.10 is never used by DHCP anyway. 

This is just a visual reminder and not necessary as part of the solutoin.

Troubleshooting

Working through the very helpful troubleshooting tips in the Hewlett Packard printer forums didn't fix the issue.  Tried the HP Print & Scan Doctor utility and the more modern Windows 10 HP Smart application using all their diagnostic features to check and fix connectivity and port issues.

Background

Then as a last resort I tried extending the DHCP lease times via telnet, since the R7800 router lacks a graphical interface to extend lease times. After extending the IP lease times to 7 days, the printer no longer drops off the network, even after the printer drops into sleep mode (power off never setting is set) and the wake on LAN successfully wakes up the printer.

Note:  If I have to reboot my printer after 7 days that is a fine compromise, I can always extend the IP address leases to a longer time like a month if becomes an annoying problem.

The issue appears to be once the printer has dropped into sleep mode it can no longer renegotiate the IP address lease with the router so then the router drops the device after a few hours from the Attached Devices table.

In theory, the IP lease times (don't know for sure) with Netgear routers are set to 24 hours before expiring.

Half way through the set time (12 hours) the device will attempt to renegotiate the lease with the router.

If the device's network card is not online and responsive (printer sleep mode) then the lease is dropped.  Once dropped no comptuer on the network with the printer driver installed can communicate with the printer as the IP address is no longer in the routing table.  The address doesn't exist so the print job cannot be delivered, making the local computer's printer driver report the printer as being offline.

Hope this background and solution helps someone frustrated in the same situation.

Aly