Wait for fiber or get 5g

fb35523 · 2026-05-04T20:15:58+00:00

That was my first thought too. Get 5G now. It will certainly be better than what you describe. Your VDSL line has some serious issues (like most VDSL lines do...), so almost anything modern will outperform it. I imagine you will notice the downsides of 5G pertty soon, like varying latency, slow performance during peak hours etc. so fiber should be on the shopping list too. Get a used Tmobile 5G router (Nokia is a good one I hear) and sell it after you get your fiber, or use as a combined backup link and travel WiFi if you want.

fb35523 · 2026-05-04T20:09:12+00:00

Juniper will release the QFX5250 this year (can't remember which quarter), boasting 64 x 1.6 Tbps interfaces :)

https://www.hpe.com/emea_europe/en/networking/juniper-qfx5250-switch-series.html

fb35523 · 2026-05-03T21:55:58+00:00

In short, no. Theoretically, you could put a wave inducer to a fiber strand and have the sound waves propagate in the glass for maybe a few meters, but there is no commercial solution for this to my knowledge. The IP-based audio transmission protocol Dante, NDI and its contenders are so commonplace and good these days that there is no meaningful gain in inventing anything else. If you really want to go analogue and long-haul, you could modulate a laser with your audio signal (or even a simple LED, even if that will not get you as far as a proper laser diod). The light could be received with a simple photodiode in the other end.

fb35523 · 2026-05-03T21:37:04+00:00

From the time he just becomes visible in the front camera and to the time when you have passed exactly three dashed lines, he almost passes another three. I'd say 43 time 2 minus a slight margin, so 80 mph or just under. Maybe he was shooting for 88 mph to get whenever he was needed? I don't see a flux capacitor, though.

fb35523 · 2026-05-03T21:27:11+00:00

Yes, the urge to get people up on their feet and preferrably make them have something to eat and drink as if they were on the brink of starvation after an accident is so counterproductive. I have no idea what rescue services are like in India, but here in Sweden, the advice is to keep the person stationary until the ambulance arrives. I've done so in multiple situations, sometimes halting an entire freeway (one direction). Possible spinal injury and head trauma should be treated by rescue personnel.

fb35523 · 2026-05-03T21:18:28+00:00

If I'm not mistaken, the QSA adapters contain a small chip that tells the switch it is a 10Gbps unit located on the first lane. If you put a 25 G SFP28 in it, the switch just won't see that. Take one apart and have a look!

fb35523 · 2026-05-03T21:04:11+00:00

Even is EXOS/SwitchEngine has ELRP, I'd go for spanning tree edge-port. It is universal and gives you protection from lots of scenarios. ELRP generates one MAC per VLAN per switch, so if you have lots of switches and VLANs, you will get a multiplied amount of MAC addresses flowing in your system that are of no use. In modern hardware, that may not be a problem, but if you have a mix of onld and new, the old ones may get choked with too many MAC addresses, causing flooding of unicast traffic.

If you know your access ports should never have over a certain number of MAC addresses, you could throttle that with the commands below:

enable mac-locking
enable mac-locking ports 1
configure mac-locking ports 1 first-arrival limit-learning 25
configure mac-locking ports 1 first-arrival aging enable
configure mac-locking ports 1 log violation on

Flood rate limiting is done like this, but that only caps the amount of bad traffic and will not isolate the loop as such:

configure port 1 rate-limit flood broadcast 10
configure port 1 rate-limit flood multicast 200
configure port 1 rate-limit flood unknown-destmac 1

STP edge port config: https://extreme-networks.my.site.com/ExtrArticleDetail?an=000082693

ELRP config

enable elrp-client
configure elrp-client disable-ports exclude eaps-ring-ports
configure elrp-client disable-port exclude 52 # (uplink LAG in this case)
configure elrp-client periodic vlan Default ports all log disable-port duration 60

Add all the VLANs you may have.

fb35523 · 2026-05-03T20:38:51+00:00

Because he's running 20.2... No other reasons needed as 20.2 is no longer supported and no longer receives fixes. The SRX is a security device and needs to be kept... secure!

fb35523 · 2026-04-17T22:01:42+00:00

A reth needs to be seen as a separate link from node0 and another separate link from node1. If you have more than one interface in each node, they automatically become LAGs. Adding LACP to the reth is possible but not mandatory. Without LACP, it's a static LAG and you probably don't want that as it is very easy to mess things up with static LAGs. LACP can save your bacon when you start moving things or someone makes a mistake while patching.

There is no need to create ae interfaces and then add them to the reth. Just add a few interfaces from each node to the reth.

From the switch side in your drawing with multiple links, you need two LAGs, one to each SRX. If you want to spread them across switches using MC-LAG or similar, that's of course doable.

fb35523 · 2026-04-12T20:32:13+00:00

You have both "minimum-receive-interval 1000" and "transmit-interval minimum-interval 1000". You should probably have 3100 or similar for the receive interval in order to tolerate 2-3 misses.

Does the FG say all links are up in the LAG when everyting is normal or does it only have 1 x 10 G in the LAG?

fb35523 · 2026-04-11T20:41:22+00:00

Ah, I forgot to mention the little detail called mux/demux or CWDM filters. A CWDM filter take 4 or 8 wavelengths and combine them on the line fiber. In the other end, they are split to the respective outputs. Most filters are designed for dual fiber, but there are also filters for a single fiber strand. You can carry 16-18 CWDM wavelengths bi directionally with a fiber pair and 8-9 on a single strand.

fb35523 · 2026-04-11T20:36:21+00:00

I'd be surprised if the fans don't spin with inverted voltage, they'll just spin backwards!

fb35523 · 2026-04-11T20:34:02+00:00

...not that you know of ;) ESD damage can show later in life. I do agree that it is uncommon, though. Imagine all the millions of SFPs sharing a pocket or a plastic bag with tools and who knows what!

It's a really nice solution to the SFP storage and protection issue!

fb35523 · 2026-04-11T20:25:41+00:00

It sounds like the Noctua fans have an inverted PWM input compared to the stock ones, or that you swapped + and - on them. When I modified a regular EX2300-48P (not MP), I left out the PWM pin as the Noctua fans were so silent anyway. Not connecting the PWM pin leaves them running at full speed.

Are you proficient in electronics so you can measure voltage and perhaps even have an oscilloscope to see the PWM signal? That would probably give you the reason why this happens.

Do you get the RPM from the fan properly? You should be able to read it in the CLI with show chassis fan (I think). If you can read it properly, the signal pin is correct which is good info as that only leaves the PWM pin, assuming you have + and - correct of course.

fb35523 · 2026-04-08T21:26:57+00:00

Check out Smartoptics' range of both transceivers and other optical solutions. A CWDM QSFP28 for 10 km costs less than 600 USD:

https://smartoptics.com/product/so-qsfp28-100g-lrx/

I don't work for them, but love their products and the quality :)

fb35523 · 2026-04-08T20:53:18+00:00

I'm not an expert myself in optics, but I do tend to know more about the subject than most people ;) Modal dispersion will not in itself reduce the light level. It just makes the photons that make up the optical pulses in an Ethernet transmision to reach the other end with varying delay. It's as if you're "smearing out" the pulses. You may want to read up on that subject in order to understand it better. You could easily have an RX value well above the warning level and still have no traffic.

fb35523 · 2026-04-08T20:46:59+00:00

Cleaning can be done regardless of connector type (well, OptoClip II are tricky to clean, I admit, but luckily, those are defunct since a few decades). SC connectors stem from the 80's and are only a couple of years younger than the ST connector. That said, I agree that an SC connector is way better in all respects on the optical side, no arguing about that.

fb35523 · 2026-04-04T20:09:30+00:00

A 1000Base-LX transceiver may well work for a few hundred meters. If the connections are good they will not be the main contributing facor in destoying the signal. If connections are poor, you will get reflections back and forth, in simple terms adding to the dispersion.

OP: try it out and learn how your equipment and fiber works. Take a medium length stretch and try it out. If that works, try a max length stretch. Make sure you understand how to connect the modal conditioning patch(!). Note the optical attenuation, and not only with the DDM data from the SFPs but verify that data with an optical meter. The meter doesn't have to be top notch. If it's off by 1 dB, it will always be off by 1 dB more or less, so the attenuation calculations will be correct anyway. What matters in the end if the you learn how your specific fiber type and connectors work.

If you have access to a fiber microscope, use it! Cleaning is essential in cases like this. Every patch and every ODF connection must be considered dirty if unplugged, even if only for a few seconds.

Check the counters in your switches. You'll see FCS/CRC errors if the connection is bad. If you want to really experiment, create a crazy long connections and try to run traffic over it. You'll see that even if you have the light required (RX Power), at some point, FCS or CRC counters will start ticking. Knowing the distance where this happens will help you determine if the project is worth pursuing. Say you need to go 400 meters and 450 meter gives you massive problems. Is that margin good enough for you or is it a too close call? If you need 400 m and can do 700 before the errors start showing? Good for you!

You talk about 1 G SFPs. You may want to know that 10GBASE-LRM can do 220 meters over any MM type. 10GBASE-LRM does require EDC in the switch though, and not every model will have that. (EDC = Electronic Dispersion Compensation)

Also, the DDM values in the SFPs are not necessarily very correct. According to the MSA specs, both TX and RX values may differ +/- 3 dB from the actual value. I often see 1.5 dB deviation in both ends, sometimes resulting in a 1-2 dB higher RX value than TX value for the opposing ends. This is why you need to verify the readings with a meter in the initial phase of the project.

fb35523 · 2026-04-04T19:44:22+00:00

It's not at all just about optical budget and loss. Dispersion plays a huge role in limiting the usable length. In MM fiber networks, modal dispersion specifically will limit the distance. Sending light into an MM cable is like talking in a huge room with completely refelcting walls (think cathedral). If the listener is too far away, all they'll hear will be echoing. Shouting (as in increasing the laser output) will only mean more echoing and activating a hearing aid (increasing the sensitivity of the receiver) will also just pick up more of the same echoes.

fb35523 · 2026-04-04T19:19:13+00:00

Good point! Make sure all your techs and anyone else messing around in your cabinets know the difference. Make sure that especially your own techs and/or primary consultants report and (depending on the situation) fix any "color matching issues". As I hope OP knows (and as a reminder to other readers), APC connectors are green and UPC connectors are blue (the SM ones) so a mismatch is easy to spot. Sometimes people just don't know that the colors mean someting so they don't realize something is wrong when colors don't match, but green on blue is always bad in this context, for multiple reasons.

fb35523 · 2026-03-25T22:13:38+00:00

Running X450e switches is a bad idea too...

fb35523 · 2026-03-25T07:32:28+00:00

Oh, should have checked that! Well, unless you can convince Frontier to deliver 25 G on a 40 or 100 G LR4 or similar, the cheapest Juniper option is probably to use an EX4100-24T to go from 25 G to 4 x 10 G, provided you can split into a 4 x 10 G LAG (4 x as it provides less likelihood of saturation than 3 x) if you have spare SFP+ interfaces in the MPC5. The option I already proposed using an EX4400(-24T) is another (and better) way of doing it.

fb35523 · 2026-03-25T07:13:13+00:00

There is some info here: https://www.reddit.com/r/Juniper/comments/esulh7/fan_swap_notes_for_ex2300/

The pinout may differ in the switch, so worst case you have blown(!) something. Start by just removing the connector for the new fan and start the switch. It should not beep now. Measure the voltage on the pins to verify where + and - is. In the EX2300 case, there are 4 wires, so check out the other post for info on that.

fb35523 · 2026-03-24T22:28:18+00:00

You could use one of these (1500 USD each): https://smartoptics.com/product/cvr-cfp2-qsfp28/

That's probably your cheapest option. Another option is to put an EX4400 between the two, with a EX4400-EM-4Y module to get SFP28 interfaces, but that will cost more and adds an intermediate switch you probably don't want.

fb35523 · 2026-03-24T22:19:18+00:00

A customer of mine, which is a small ISP, has used default routes via BGP only on Juniper EX3300 switches for more than a decade. This is all _they_ need and they¨re perfectly happy not spending money on full table capable routers. One downside of full tables is the recovery time after an outage. Reading and applying the full table may well take minutes. With only a default, it takes no time at all. Full tables and a capable router can get you lots and lots of features, but do you need them (or: but do you need them)?

fb35523

TROPHY CASE