Yesterday I was switching over to fiber networking and CRS305-4S at home and tried 10g between two hosts on the ports.
I was getting very inconsistent speeds and moreover, a lot of rx errors.
At first I thought maybe the bend is too tight on this short fiber (and indeed, had direct connection between two computers a day before and fixing the little bend did help).
But no, that didn't help this time. I thought, okay, let's use MM fiber with MM SFP+. As a matter of fact, I do have slower 1 gig computers sitting on MM SFP+ with SM fiber and have no problems there.
Well it turns out that replacing it with the correct, MM fiber solved all the rx errors entirely and speed went to consistent 10G. Now, why I did this. I read somewhere that you can use SM fiber with MM transcievers but not the other way around. I can attest that the advice is technically correct, in a way, using SM fiber on MM network DOES indeed work, but not as fast as it should lol.
That reminded me of a story back when I was a kid and could only buy a 3m ethernet patch cord with my pocket money, to try and play an FPS game with my friend at home. 3m wasn't that long so what I did back then was... cut the cable I had and extend it using JUST ABOUT ANY WIRES I could find in my house. Two strands were made from a power cord, two with a phone line cord, four others with some other wire I had lying around.
The funny thing is it did work. With glitches and dropouts, sometimes requiring me to go check and move the cable around a bit... Also, because I knew nothing about the networking back then, we had to wait for windows to auto-configure the 169.254 addresses on both ends(that takes several minutes) and one of us would relay that in order to connect.
What a fun time it was.
Use the right tools to do the job. SM fiber with MM transcievers does NOT work well at all.
I was getting very inconsistent speeds and moreover, a lot of rx errors.
At first I thought maybe the bend is too tight on this short fiber (and indeed, had direct connection between two computers a day before and fixing the little bend did help).
But no, that didn't help this time. I thought, okay, let's use MM fiber with MM SFP+. As a matter of fact, I do have slower 1 gig computers sitting on MM SFP+ with SM fiber and have no problems there.
Well it turns out that replacing it with the correct, MM fiber solved all the rx errors entirely and speed went to consistent 10G. Now, why I did this. I read somewhere that you can use SM fiber with MM transcievers but not the other way around. I can attest that the advice is technically correct, in a way, using SM fiber on MM network DOES indeed work, but not as fast as it should lol.
That reminded me of a story back when I was a kid and could only buy a 3m ethernet patch cord with my pocket money, to try and play an FPS game with my friend at home. 3m wasn't that long so what I did back then was... cut the cable I had and extend it using JUST ABOUT ANY WIRES I could find in my house. Two strands were made from a power cord, two with a phone line cord, four others with some other wire I had lying around.
The funny thing is it did work. With glitches and dropouts, sometimes requiring me to go check and move the cable around a bit... Also, because I knew nothing about the networking back then, we had to wait for windows to auto-configure the 169.254 addresses on both ends(that takes several minutes) and one of us would relay that in order to connect.
What a fun time it was.
Use the right tools to do the job. SM fiber with MM transcievers does NOT work well at all.
