Hi,

My 450G seems unable to negotiate gigabit connections to another switch. Symptoms: link goes up and down a number of times,
connecting at 1G, and then settles down using 100Mbit connections. This happens with multiple switches (one HP, one Netgear), but not with an Acer laptop that has a 1G interface.

I reset the configuration, and added a static IP to a single interface, to keep things simple. No change.

Any ideas?

Gé

Are all 450G ethernet interfaces affected? Have you tested with multiple cables?

Yes, and yes. I tried:

- multiple cables (all cables are Cat. 5e and work fine between other devices at 1G)
- multiple interfaces
- including and excluding ether1 from the switch.
- two different switches (HP Procurve 1800-8G and Netgear GS105NA)

Strangely there was no problem negotiating a 1G link with a Acer laptop (Aspire 1410) on any port.

OS version = 4.15

Anything I can try?

Thanks,

Ge'

I have a netgear GS105V2 and it seems to be VERY fussy about what it will talk to at 1Gbit/s although I'm unsure if the one I have was faulty, someone gave it to me but the original Psu was faulty (failing under load). According to the power rating it should work with a 12V 1A psu but when I tried it with one from a DG834 router it seemed to behave a bit oddly.

I've also found certain realtek NIC's hate my plexus 8 port unmanaged switch I use for my desktop/Nas and will often refuse to talk to it at Gbit/s speeds where as everything else with a Gbit/s interface seems happy enough to.

I see autonegotiation problems with 450g and Motorola Ptp600.
Both have Gigabit Ethernet but at some times they go down
to 10mbit. Disable/Enable port on 450g brings them up to
Gigabit again.

I have a procurve 1800-24 and a couple RB450gs attached to it. They sync up at 1gbit no problem. Shot cat6 cables, like 12"... But any reasonable distance should work.

Hi, I too have seen problems.

I am connecting a 450G to an MRV switch and also tested with a Zyxel GS2024 switch. When I set the Auto neg off on the RB and force 1000Mb/s FD then I do not get a sync. I have tried setting the switches to auto-neg and forced-neg and I still cannot get a link when the RR450G is auto-neg off. If the switches and the RB are on auto-neg then I get 1000Mb/s

However, I have then seen strange results when doing a bandwidth test through this link. I set the BW tester to push traffic at 100MB and I see 100Mb/s of traffic TX and 23Mb/s RX (strange).

If I set the auto-neg off and 100Mb/s FD I can pass 100Mb/s both ways TX/RX.

Something is not working. I am open to suggestions as I have tried loads of combinations and changed the patch leads too.

1Gbit link requires auto-negotiation enabled at all times, other way 1Gbit link should not work. That is as per RFC. This is due to attributes that has to be negotiated and that are not speed and duplex setting. 100Mbit link only negotiates these two settings, therefore it can be forces to that speed while 1Gbit cannot.

If you are checking 1Gbit, make sure you have high quality 5Cat-e (basic 5Cat will not work) wires or 6Cat.

Im having this same issue with equipment I co-located at 2 different data centers. Both have a 450G in-front of the server, BOTH are NOT ABLE TO LINK at 1gbit. At one datacetner they even ran a BRAND new cat6 cable to no avail. Ive tried every Ethernet port setting, on both sides, the link never comes up.

Ive also seen this at home before with my 450g and more consumer grade equpiment.

Clearly there is an issue that MT needs to address and its been way to long since this has been addressed.

both 450gs are 4.17

and ofcorse both data-centers had no problem hooking their crash carts or laptops up to the link in question at full 1 gbit, so whats the deal Mikrotik??

it is not clear what settings you could try to set up as for 1Gbps link to work correctly you have to leave it set to auto-negotiaton or else all parameters of 1Gbps link will not be negotiated and link will not work.

You can try to add some 1Gbps switch in the middle to see if devices will negotiate 1Gbps successfully then.

I myself have 2 RB450G connected to my PC and to RB1000 and RB800 connected with various cables with different length and i had never had issues with 1Gbps link negotiation. And i can assure you that i have used every release of 4.x and 5.x (including betas and rc on both) on these.

Sorry to resurrect such old topic, but I seems to face same problem.
RB450G renegotiate 1Gbps connection too often.
Test case: RB450G, switch-all-ports=no, ether1 connected to 100Mbps DLink switch, ether2 connected to MacBook Pro. Initially after boot RB450G negotiates 1Gpbs link with MacBook. Link stays stable for near half an hour (with or without traffic), after that time ether2 starts renegotiations (3 to 5 times, v4.17 have silence in logs, v5.8/5.11 shows many 'interface down/up' lines) and link stays at 1Gbps. This scenario could repeat 2-3 times with 5-10 minutes interval. At last after near an hour after power on - ether2 negotiates 100Mbps and stays stable on it.
Sometimes after such renegotiation on ether2 - ether1 goes down, and only enable/disable of ether1 could return it online.

Tried with different cables and port configurations (setting ether2 as master for ether3-5, for example) - same situation

RB450G renegotiate 1Gbps connection too often.

Could this be related to poor PSU unit or high current usage?
My tests shows that running RB450G with PSU from old notebook (19V/3.6A) eliminates all visible problems with Gigabit renegotiation. While running from common PSU (15v 1.2A) - could work stable only with 100Mbps connections.
Both PSU have more capacity than RB450G require (6-12W?) - so maybe gigabit speeds require more power?