SFP+ optical transceiver as one of the most commonly used fiber optic products in fiber optic communication applications, also goes by SFP+ optical module, can be purchased in many markets and ways online or offline. According to most customers who bought SFP+ optical modules and sellers who sold SFP+ optical modules, the most confusing problem they confronted is it’s not easy to say who should be responsible the breakdown that found with the delivered SFP+ optical module. Also, for some users who have applied the optical module for a certain time, it found difficult for them to figure out the reason when a sudden breakdown happened. This post will definitely bring you some clear ideas about how to get the specific reasons for the SFP+ optical modules that stop working or don’t work, and what to do with the out-of-work SFP+ optical module.
The first thing to do before you communicate with the seller or technician is to know the reason when you find the SFP+ module is not working, then you can have a clear idea who would be responsible for it and the communication would be more efficient as well. So you are supposed to know what could cause the malfunction of SFP+ module.
What could cause SFP+ module fail to work?
First of all, the basic information you should be aware of is the issue of a failed optical module must lie in either its hardware or the software. Basically, software issue will directly result in the compatibility issue, and hardware issue can be resulted by multiple reasons.
Most of the providers or sellers ensure you a full compatibility, and this may not always be true. Sometimes the device can’t be compatible, and you may find yourself troubleshooting it without any concrete result. Because the new transceiver you buy is likely to have been manufactured by the current new technologies, then possibly it is not compatible with your infrastructure which is partially old. In this case, it is advisable that you consider replacing the device. Besides, that should remind you of a careful selection and full communication with the seller before you pay for it.
Transceivers hat have compatibility issues may display the following error message. “% GBIC_SECURITY_CRYPT-4-VN_DATA_CRC_ERROR: SFP+ in port 123456 has bad CRC %PM-4-ERR_DISABLE: gbic-invalid error detected on Gi2/1/20, putting Gi2/1/20 in err-disable state.”
1) The optical port of SFP+ module being polluted or damaged. This would increase the loss of optical links so as to block the transmission. There are 4 possibilities for the pollution or damage:
- SFP+ module ports have been exposed to the environment and polluted by dust or moisture.
- The end face of the fiber patch cable which is connected with SFP+ module has already been polluted, this caused the re-pollution happen to the SFP+ module port.
- Improper operation when using the optical ports of fiber pigtail caused scratches on the end face.
- Using low-quality fiber patch cables or fiber pigtails.
2) ESD damage happened to SFP+ module. ESD can adsorb dust and change the resistance between links, so as to influence the performance and lifespan of SFP+ module. In addition, the heat generated by ESD would damage the components to stop working. Thus, in addition to enhancing the ability to resist ESD, more importantly, correct operation is also helpful for protecting components from ESD.
Three aspects may result in ESD damage:
1. Dry environment makes ESD easily happen
2. Improper operation of SFP+ module. For instance, operating SFP+ module with electricity; contact the ESD-sensitive part of SFP+ without anti-static protection; free of the anti-static package for SFP+ module.
3. Without grounding or imperfect grounding for active fiber optic devices.
3) SFP+ module APD burned out. There are two important reasons for APD burning out that are often ignored by customers:
- Short Distance connection.
- Lack of attenuator.
Once testing the transceivers, there must add the attenuator. If it is CWDM SFP+ transceivers that have two channels, the attenuator is needed in each channel. Otherwise, short distance connection without attenuators added is very likely to cause APD burn out inside. Lack of anti-static protection or operation would damage the electrical components as above mentioned.
How to troubleshoot the SFP+ module?
Once you find the malfunction, then what you need to do with the failed SFP+ module is just to troubleshoot it. An effective troubleshooting can help you find out the root reason for not working, that will guide you an efficient communicate with the seller or what to do next for the maintenance. Here are some useful methods for troubleshooting the SFP+ module:
- Check if the fiber patch cable used is conforming to the fiber optic transceiver.
As we know there are some specifications like colors, fiber types, single mode or multimode to differentiate fiber patch cables, same for optical transceiver modules. So check if you used a correct fiber patch cable to connect the fiber transceiver modules and confirm they are aligned to work mutually and then the connection is not the problem.
2. Self-circle inspection
Connect the transmitting port to the receiving port by fiber patch cable, and then check if the switch works. If the switch can work, the optical module is not the problem; if not work, and then the optical module has a problem.
3. Ports configuration
If above inspections don’t work it out, and then you need to go to next step that set port working pattern. Most commonly used switches are with the ports of photoelectric type, and most of the optical ports stay closed, which need to be opened manually. But for the communication between different brands’ switches, you also need to set the ports speed and working pattern to 1000Mpbs and full-duplex mode.
In order to detect compatibility issues, most of the transceivers have a burned-in chip that contains information such as the serial number, the security information, and the vendor ID. If the information does not match what is contained in the database, the device will be disabled making the device stop working.
Things you need to be extra careful with optical module：
- Select a reliable provider for the optical module and related fiber optic products，like Cozlink.
- Stop getting the optical module and the related connectors polluted or damaged, you can refer to the reasons source above.
- Keep a good knowledge of correctly installing and operating optical module in mind.
- Fulfill the ESD resistant measures; reduce environmental influence as much as possible on the optical module.
- Get correct connections.
To sum up, complaining is not a good way when there is something wrong with your SFP+ optical module, what is more helpful for the situation is to detect the reason in the correct way as above mentioned, in the course of detecting, it’s better to make records or take photos for the evidence you get, then communicate with the seller or ask for a technician to maintain according to the reason, that will be the most efficient way to get your device right.