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16

I don't think the default gateway has anything to do with your problem. Local traffic between two devices on the same subnet doesn't flow through the default gateway and in any case the speeds you are reporting for your local traffic are 10 times higher than the speed you report for the link to your default gateway. A couple of possibilities spring to mind. ...


12

Have you looked at using a separate external mux? I've run parts of our rings on pairings of ordinary (but colored) 10G optics and passive CWDM muxes with a single strand on each side. This let us also do multiple parallel links at the same time (we used 8 channel muxes).


11

You can use short range SFP optics for this. The Cisco part number is GLC-SX-MM, and the cost is about $75-$100 each (you'll need two). The person installing your fiber should use 50uM multimode fiber (62.5uM is also useable, but you're getting close to the maximum range) with LC type connectors.


10

Just to address the SNMP portion of your question, I'm guessing that you are seeing the 4.3Gbps result from querying the SNMP object 'ifSpeed'. If so, you are simply getting back the maximum value that is possible from a 32-bit object (i.e. 2^32-1). This is the expected behaviour for a 10Gbps interface. You will need to query 'ifHighSpeed' for the interface ...


10

Wavelength and rate are the two big ones. As you're dealing with 10G ethernet, rate isn't in question. (if we were talking about fibre channel, or SONET, then it would matter.) For your specific case, they are providing service through a 1310nm "LR" (long-reach) interface. The "SR" (short-reach) optics will not work -- wrong wavelength (850nm) and wrong ...


10

Do I need to protect the physical empty SFP port? What's a good way to do so? Empty SFP slots should be covered when not in use, so no dust is sucked up by the system fan - depending on how dusty the environment is, pressure of the fan etc, this isn't required at all times. Do make sure the slot is clean before inserting a module though. You can use just ...


9

Short answer: in theory yes, in practice no. Long answer: There are SFP+ optics which can also work at 1 GbE, I've talked (sorry, no other source than that) to people who were experimenting with it and were able to get it running. Unfortunately it is highly dependable on the device you plug the optics in, i.e. not every device in the test was able to tell ...


9

That switch uses (Q)SFP+ ports which are essentially PHYless. You need to either use matching PHY type transceivers on both the switch and the host ports (e.g. 10GBASE-SR or 40GBASE-SR4) or direct-attach cables that are compatible with both sides. The Mellanox NIC has QSFP28 ports that should support QSFP+ modules as well - check the documentation. Note ...


7

Spanning-tree is spanning-tree no matter which ports you use.


7

Yes you can uplink different brand of switches using SFP. The term stacking in this context means that several switches act as a single one. This is always a proprietary (and model dependent) feature, and can be done only with switches of the same brand (and not all of them). SFP doesn't work only with fiber: there SFP to copper converters, so you can ...


7

SFP modules are overwhelmingly sold without a patch cable. In fact, I've never seen an SFP transceiver being offered in a set with a patch cable. In addition to the existence of various connector types - LC, SC, ST being the most common - there are multiple end faces - SPC or APC - and some transceivers may even be used with single-mode and multi-mode ...


6

Maybe these bugs are affecting you: CSCuj74167 (Gigabyte link from WS-C2960X-48FPD-L not coming up when using GLC-SX-MM) applies to you. Fixed in software release 15.0(2)EX4. CSCul88801 (1G or 10G in uplink ports of a Catalyst 2960x stack may not come up after a reload or OIR of SFP/SFP+. 1G or 10G SFP appear as “unknown” in the output of the show int ...


6

A passive wavelength-division multiplexer, such as a CWDM or DWDM mux, would probably be your best bet; this is how Service providers supply fiber especially longer distances from their local Hub site. It is probably a larger investment upfront but it would also allow you to get more out of your existing leased fibers. This is also assuming that your lease ...


6

Your ethernet SFP/SFP+ for fiber are going to be 1 or 10 Gbps. There isn't a 2 Gbps ethernet fiber SFP (some vendors used to count this way because of full duplex, but it is still 1 Gbps in each direction). You may be able to use LACP, depending on the switch vendor/model. Combining multiple interfaces into a single channel is really just fooling STP to ...


6

I'm afraid the real solution is to use either Cisco transceivers or third-party transceivers - from reputable vendors- that are specifically "tagged" to be used on Cisco switches. Using random transceivers will only cause troubles and the time you will loose will vastly overcome the economy made on the hardware. Edit: As you can see in this datasheet the ...


6

QSFP+ is just the transceiver interface. Medium compatibility and reach is defined by the PHY used by the fitted transceiver. While the short-range 40GBASE-SR4 PHY requires four separate multi-mode fibers per direction (OM3 or OM4), 40GBASE-LR4 (CWDM) or -FR (single-lane) use only one fiber per direction - both require single-mode fiber, however. Both will ...


6

Cisco writes the following about the dust caps: For optical SFP transceiver modules, before removing the dust plugs and making any optical connections, observe the following guidelines: Always keep the protective dust plugs on the unplugged fiber-optic cable connectors and the transceiver optical bores until you are ready to make a connection. ...


6

You need a breakout cable - MPO to 8x LC. The reach of the cable depends on the PHY that is used, e.g. 400 m for 10GBASE-SR over OM4, or 10 km for 10GBASE-LR over OS2. Make sure that the transceivers on each end support matching PHYs, that the QSFP+ port supports breakout in your scenario, and that you match the breakout/patch cable type to the fiber type. ...


6

As per IEEE 802.3 Clause 38, 1000BASE-SX requires OM2 (500 MHz·km for 850 nm) for max. 550 m reach. As a superset, OM4 is fine as well (there's little point buying OM2). With 10GBASE-SR the reach over OM4 is reduced to 400 m, so you're also good for an upgrade later on. There's also OM5 but it's only for higher speed WDM, not for longer reach with 850 nm. ...


6

SFP is a standard for modular network ports. Essentially, the empty SFP slot is "PHY-less" until you plug in a module - with an Ethernet SFP port, you can plug in a 1000BASE-T module for twisted pair, 1000BASE-SX for multi-mode fiber (550 m max.), 1000BASE-LX or single-mode fiber (10 km max.), or various others. Fiber comes in two basic types: multi-mode/...


5

You don't say which switch you are replacing nor specify the type of transceiver it has (you only specify the connector). However, the only 24 port Cisco switches I know of personally that have 100Mbps MT-RJ ports utilize 100base-FX, but make sure you double check. Will this switch support 100/1000 or 1000 base only? According to the Cisco 100-Megabit ...


5

Little late to the website so you may have moved on but, We use Solarwinds. Under the edit node properties there is a check box for 64-bit counters. It is probably not checked. Seen the problem you've described for some non-Cisco products in Solarwinds. Also from the manual for some manufacturers. If the added node supports 64-bit counters and you want to ...


5

You can check Cisco SFP Modules for Gigabit Ethernet Applications Data Sheet There you can see that 1000Base-SX SFP (part-number GLC-SX-MM) using 62.5 um MMF reaches 220 or 270 meters (depending on modal bandwidth of the fiber). However, if switches are 200 meters apart it could be easy that cable runs are actually longer than 220 meters. Of course, you ...


5

from comment HPE switches with pre-16.x firmware require original or HP-compatible transceivers. A transceiver that's not HPE branded is not activated when inserted, as indicated by LED and in the device log. You don't necessarily need an original HPE module, there's a large "compatible" market with SFPs that electronically claim to be original. With 16.x ...


4

Quick test: Swap the SFPs with a known working ones on the switch (if possible) and see if the condition stays with the ports or follow the SFPs. If the other SFP works in the current "problematic SFP ports" there is less possibility of this being the switch's problem (I still could be, but just unlikely). You can try to plug it in the other switch's too......


4

Multimode fiber has a bigger core and uses less precise optics than singlemode fiber. This makes the transceivers (SFPs in your case) cheaper than their singlemode counterparts. This also means they can't shoot over as long of a distance as singlemode can because the light gets scattered within the fiber and has poor long-range characteristics. OM3 is a ...


4

I have used a variety of SFP modules (including Ciena, Finisar, Cisco, Fiberstore.com...) in a Zyxel MGS-3712F without any issues.


4

Comments converted into answer: Please spend a bit of time learning the actual terminology rather than inventing your own, which confuses both you and us. An SFP (small form pluggable) is not a connector. It typically HAS one or more often two female optical connectors as part of itself, but what it IS is an electro-optical transceiver. The 10 Gig ones are ...


4

There's several advantages to Fiber-to-the-desk length: copper cabling is limited to 90 meters of horizontal cabling (leaving 10 meters for patching). Fiber doesn't have this limitation. In some building this can make a difference cabled once for all: upgrading from 1Gbs to 10/50/100Gbs or a future Tbs doesn't require to recable the building, the fiber ...


4

SFP+ modules leave more circuitry to be implemented on the host board whereas XFP or XENPACK implemented those circuitries inside the module. Normally, you don't have to know that because you just plug the correct device in the corresponding hole SFP+ are a little smaller, and the module can be backward compatible with 1G SFP (if device allow it, which ...


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