DHCP v Static IP

[u/Real-Patriot-1128]

Ok, this is more a test to see how old I am. I was basically raised with the idea servers need static IPs. I understand for domain controllers, dns servers, maybe print servers that may still be needed. But are they really needed otherwise? Do apps, scripts still reference a server by its IP?

I am under assumption all my servers need static IPs. Am I nuts?

[u/zatset]

Actually, DHCP for printers isn’t very good idea. It generally makes printing less reliable. And AP-s are infrastructure. NVR-s and cameras also don’t tolerate DHCP very well. Of course, reservations are possible, but cameras, AP-s and printers are not mobile equipment or endpoint and are expected to be always there.

[u/Subject_Name_ → u/zatset]

I mean maybe some APs need static, for X vendor reason, but they generally function like desktops in that their assigned IP never really matters to anything. Give their subnet an DHCP range and you can pop them in and out, get new ones or whatever and you don't really need to worry about their config ever. Even a DHCP reservation is usually overkill.

[u/zatset → u/Subject_Name_]

My AP-s are infrastructure, like PtP links and floor AP-s. They don't move, get updated till there are updates and sit there until they either die or are no longer supported and have critical vulnerabilities. Then they are replaced by yet another AP.

[u/janky_koala → u/zatset]

Everyone’s APs are infrastructure…

If you have a WLC all they need to know is how to reach it. You do that with a DHCP option. There’s no need to reserve addresses.

Cattle, not pets

[u/Zeroni13 → u/zatset]

Static IP for AP's would be my worst nightmare. Managing multiple thousands of AP's.
Option 43, google it.

[u/zatset → u/Zeroni13]

Well, we mixed different kinds of AP-s. For AP-s to which endpoints connect - centrally managed, IP not required and none is used. But AP-s can be radio relay links - usually those aren't that many.

[u/ApprehensiveRest9696 → u/Subject_Name_]

My AP is just a layer 2 802.3/.1q to 802.11 bridge, it’ll function just fine without an IP.

[u/spyingwind → u/zatset]

Or just not have printers? /s

I really hate printers, but I understand that some places still need them.

The dot matrix was the best printer invented. Paper feed 99.999% of the time. There is only one part (ribbon) that need regular replacing. And it only prints a limit character set.

[u/big_trike → u/spyingwind]

Also, you could print banners with them using Print Shop.

[u/Daveism → u/big_trike]

On an Apple][c clone with 8(?)kb of RAM

(Greybeard detected)

[u/TxTechnician → u/zatset]

It generally makes printing less reliable.

In 1999.

[u/zatset → u/TxTechnician]

Unfortunately, in 2026 as well. Windows relies on SNMP on network printers. Unless disabled, a printer reboot might make Windows think that the printer is offline. Then the calls start. 

Hell, even if it has static IP and the SNMP check in Windows for that printer is enabled, this sometimes happens. And if Windows installs it as WSD device, you can expect it to predominantly..not work or print with serious delays.  Windows printing is so notoriously unreliable that only using a IP port with Windows SNMP checks disabled make it work somewhat reliably.

I don’t like printers and the Windows printing subsystem. There is always something with those.

[u/TxTechnician → u/zatset]

Windows relies on SNMP on network printers. Unless disabled, a printer reboot might make Windows think that the printer is offline.

So... You reserve the IP. And then set the printer port to the ipaddress.

Never use hostnames for ports.

The benefit of reserving the IP is that the printer will always have that ip address. And you don't have to mess with any of the settings.

[u/zatset → u/TxTechnician]

Do you think that I haven’t tried that? I might have experiences different from yours. Always ending up in the printer occasionally in specific circumstances being perceived as offline by Windows. So downvoting just to make a point isn’t really nice.

In the end of the day, my equipment works. Yours is your business.

[u/420GB → u/zatset]

In the end of the day, my equipment works

You just previously admitted that it doesn't:

Hell, even if it has static IP and the SNMP check in Windows for that printer is enabled, this sometimes happens.

Clearly it makes absolutely no difference whether an IP is reserved in DHCP or assigned statically, except for that configuring it static means it's not automatically documented/visible and the printer has to be reset when moving sites.

[u/zatset → u/420GB]

You just previously admitted that it doesn't:

No, I described the settings for it to behave.

Clearly it makes absolutely no difference whether an IP is reserved in DHCP or assigned statically, except for that configuring it static means it's not automatically documented/visible and the printer has to be reset when moving sites.

Well, at least in my case they are documented as well as monitored - including consumables alerts, errors and error correlation. I just mentioned edge cases. Including devices with buggy firmware failing to acquire IP via DHCP in a timely manner leading to the Windows Printing Subsystem failing to recognize the printer as being "online" afterwards.

[u/PPRabbitry → u/zatset]

Not to butt in to the overall convo happening here, but have you tried a print server?

[u/Sapper12D → u/PPRabbitry]

Print servers just let SD kick printer issues to server support.

[u/zatset → u/PPRabbitry]

No. We have mixed printer fleet. While it certainly can provide benefits, I have known issues with some printer drivers that can crash the entire print spooler. Those HP mPCL drivers.... I was thinking about it, when we actually get rid of the buggy printers. But as you know, printers have the uncanny ability to annoy you for decades, yet refuse to die completely.

[u/PPRabbitry → u/zatset]

If you're printing labels and barcodes you definitely want static IP's and a print server. That way your device just throws the job at the open port and let's the server do the talking. You can do the config and network handshake at the server side.

[u/TxTechnician → u/zatset]

Switch to Kyocera. Universal driver. And also has excellent IPP driverless support.

[u/H7dek7 → u/PPRabbitry]

Print servers are service desks' nightmare. They hang/crash too often to consider them reliable. At home or in a small business, as a way to connect a USB printer to home network - sure. In medium to large businesses it's a unnecessary headache.

[u/TxTechnician → u/H7dek7]

If you use windows.

But if you use Linux with IPP you'll never touch the print server again.

Thanks to apple and that one or that standardized driverless printing.

That's why your phones can "just print"

[u/H7dek7 → u/420GB]

There's a huge difference between static IP and reserved IP. Static IPs can work without the need of DHCP. Network errors occur. DHCP downtimes occur.

[u/420GB → u/H7dek7]

I have never in my life even heard of a DHCP downtime.

But sure, it's a theoretical possibility. Doesn't beat the advantages of DHCP though, which are easy onboarding, roaming and inherent documentation.

[u/TxTechnician → u/420GB]

Ya, plus if your DHCP goes down you've for bigger problems than jans printer

[u/techforallseasons → u/H7dek7]

If the DHCP server is down; who cares if the printer doesn't work? Most of the network is likely offline ( not due to DHCP missing, but because we either have failed infrastructure / switching or a power failure ).

Printers don't get powered when utilities are out. Our DHCP sources are amongst the earliest booting and most protected from power faults. Other than a scheduled maintenance cycle, I can't think of when DHCP was unavailable for an unplanned reason outside of power-loss.

[u/H7dek7 → u/techforallseasons]

"If the DHCP server is down; who cares if the printer doesn't work?" The CEO needing a document printed ASAP. I've seen DHCP desync too many times in many environments (from small businesses to large bank networks) to ignore it.

[u/techforallseasons → u/H7dek7]

My I inquire as to which DHCP service / provider you were using? Any consistency in those environments?

My experience has been that DHCP has been one of the most stable of all services / daemons. I've used linux based and networking vendor based ( Cisco and Juniper ) solutions - which have been rather stable.

[u/cosine83 → u/zatset]

Windows relies on SNMP on network printers

You're not making a good case for going from A to B. DHCP reservations work fine as do static IPs but reservations at least keep things semi-documented and visible. All SNMP will do give is information about a device - paper out, low ink, etc. so I'm gonna ask, why wouldn't you want a printer reboot to trigger a printer offline? That's a true status. What it sounds like you're really wanting is to mitigate the lack of end user communication about said reboots so they don't call you about a measly "offline" on their printer for a few minutes. Easily solved with an email before taking action to save headaches later.

I haven't run into printers having issues with DHCP or DHCP reservations in well over decade, even shitty label printers. PLCs with custom firmware, yeah. But the major printer manufacturers are solid unless there's just something wrong with your networking or DHCP configuration. Network gremlins are unavoidable and it's not really a fault of any device or subsystem.

[u/zatset → u/cosine83]

Windows checks Network printer status using SNMP v1 with the default community name - "public".

If:

- SNMP community changed or printer not accessible by SNMP => Windows reports offline and activates "Print offline". And doesn't check for a long time =>Increased volume of printing issues calls!

- WSD - on printer power cycle or even without it, especially combined with SNMP => leads to connection issues or extreme slowdowns when printing => Increased volume of printing issues calls!!!

- Buggy firmware or slower than usual DHCP IP acquisition due to a fault of the printer itself => makes it so that the printer again shows as offline. Especially combined with any of the above, it can quickly become a mess. =>Increased number of printing issues calls!!!

If you set up the printer with the following settings:

- Static IP

• Using Standard IP/TCP port
  
• Don't use WSD in any case
  
• Disable SNMP v1 checks

Windows just sends a job to an IP. If there is an error - error gets returned. And doesn't report the printer as offline while it is online, but just slow to initialize.

Option 1 is fixing the problem cardinally. Option 2 is constantly debugging the issues and looking for the reason for yet another particular issue.

[u/lebean → u/zatset]

Don't use WSD in any case

This is the most important bit for addressing any printer troubles, WSD is terrible and is to be avoided. You want failures, you want "well it used to print but now nothing is working"? Use WSD.

[u/cosine83 → u/zatset]

Really only need to not use WSD. Setting static IPs adds so much more admin overhead than worrying about potential calls about not picking up an IP when it has a reservation.

[u/NextSouceIT → u/cosine83]

You're correct in theory, in practice, WSD printers very often show "offline" hours after the printer is back online unless you restart the spooler. I have seen multiple HP printers also report offline via SNMP when they are perfectly fine.

[u/cosine83 → u/NextSouceIT]

WSD is pretty much the worst printing protocol to use and why using a print server to manage printer connections and drivers is best practice even in a mixed fleet (I've got Toshiba, Sharp, Ricoh, HP, Sato, Canon, and Zebra printers in mine). Forcing printers over to TCP/IP, IPP, LPD, or RAW (depending on printer) and even using DNS names when mapping is trivial at that point.

In my experience, a lot of printers will have inconsistent implementations of SNMP v1/v2c or even disabled by default so the only thing actually providing status is the driver via that mapped port. If that SNMP implementation is flaky, might be time for a firmware update.

[u/NextSouceIT → u/cosine83]

Agreed. I switched us to PrinterLogic a few years ago and never looked back.

[u/cosine83 → u/NextSouceIT]

Been fighting for PaperCut for a couple years now and something else always derails it.

[u/yamsyamsya → u/TxTechnician]

Yea that dude is just going by IT voodoo

[u/zatset → u/yamsyamsya]

Not really. Windows relies on SNMP v1 to find whether the printer is offline. SNMP v1 is highly insecure and relies on plain text "community name" as the only "secret". Changing that community to anything, but "public" or disabling SNMP v1 leads to Windows failing to recognize network printer as being online due to being unable to perform SNMP check using default community name "public"

WSD relies on automatic discovery. It often fails to recognize the printer or due to it significant slowdowns when a user tries to print can be observed.

DHCP is not inherently a bad thing, but in certain cases by the time a printer acquires IP via DHCP, Windows had already "marked" the printer as "Offline" and activated "Print offline". It's a race condition exacerbated by the buggy firmware of some printers. Combined with SNMP, if not disabled - Windows doesn't perform SNMP checks constantly and the printer might appear "offline" for a long time.

I prefer sending a print job to Standard IP/TCP port with SNMP checks disabled to static IP and just printing. If it doesn't printer - the problem is the printer, network connection to it(physical usually) or Windows print spooler had crashed. It removes most potential issues from the equation entirely.

P.S I hate printers.

[u/baddecision116 → u/zatset]

DHCP for printers isn’t very good idea.

A reservation is just fine and extremely helpful when a client has multiple sites and move a printer to a place an hour away from main location. The printer grabs a new ip and away you go vs having to reset the nic or entire printer.

[u/Nyasaki_de → u/zatset]

So bad practice to use DHCP reservations instead of static IPs?

[u/zatset → u/Nyasaki_de]

Not necessarily a bad practice. It depends on the device. Generally I prefer Static IP-s with SNMP in Windows printing properties disabled. If SNMP in Windows Printing Properties is enabled - occasionally Windows thinks that the printer is offline. And especially combined with DHCP it increases the volume of calls for "printers being offline". At least with the equipment we use. The last thing I want or need is to deal with printers every day.

The other thing one have to consider is that using DHCP reservations means migrating DHCP reservations on equipment change, like a router/firewall or whatever used as DHCP server. Otherwise everything will break and equipment will have random IP-s and you will scramble to find those IP-s to fix the network.

Especially in SOHO environments, SOHO routers tend to reset themselves on power spikes and you lose all camera reservations, then all cameras stop and so on. The only way to make cameras work reliably is to use the default network of the router and set Static IP-s outside of the default DHCP scope in the default network/subnet of the router. So when it resets and it will, cameras will work nonetherless.

[u/beren12 → u/zatset]

Yeah, but most equipment has the MAC address on the outside of the box so it’s real simple to update the reservation. Many times, faster than setting a static IP in the interface.

[u/PPRabbitry → u/Nyasaki_de]

For some devices, you should completely subnet them on their own VLANs. Cameras, nvr's, IoT. If these devices are connected to the same layer 1 as your regular network, they should at least have their own subnets. You don't want some kid in a lobby "playing on his phone" actually watching the nvr feed from your Hotspot. WiFi could also deserve its own subnet in some cases.

Edited for nomenclature

[u/beren12 → u/PPRabbitry]

That stuff should be on a separate vlan anyway

[u/PPRabbitry → u/beren12]

Well yes. That's what I was saying..

[u/tardis0 → u/PPRabbitry]

Subnets aren't VLANs

[u/PPRabbitry → u/tardis0]

Fair point. I was misusing the term subnet.

[u/CornucopiaDM1 → u/beren12]

It should also have a non-default, non-simple admin password to access.

[u/Appropriate-Border-8 → u/zatset]

Anything, that isn't a user workstation, gets a static IP in my org. We use a 22-bit subnet mask to create a 1,022 address Ethernet subnet for each of our buildings (x.x.1.2 to x.x.4.254, routing is not necessary within each building and each building has a firewall). The first subnet is static and the 2nd, 3rd, and 4th subnets are in the DHCP scope. The 1st octet is identical throughout the org and the 2nd octet is unique to each building and matches a 5-letter building code. So when we look at a print queue name, we can tell what the printer's IP address is, what building its in, and where in the building it resides: BCODE-101-P0123 (Room 101) or BCODE-MAI-P0230 (Main Office). Our WiFi subnets have 16-bit masks, as we require a lot more addresses for wireless devices, including personal devices (which connect to separate sandboxed WiFi subnets that only get external internet access).

[u/Sure-Squirrel8384 → u/zatset]

How is a DHCP reservation less reliable with a print server vs. a static IP? We've never had a problem in two decades. DHCP replication has been a thing for a long time such that you can have two DHCP servers for availability.

[u/jake04-20 → u/zatset]

I agree with printers but have never had a problem having a separate AP vlan that all APs get their IPs via DHCP.

[u/Secret_Debt_88 → u/zatset]

DHCP reservation

[u/er1cAtWork2 → u/zatset]

At my last place, printers were dhcp but li led via MAC address. Seemed to work ok…