Fwd: is this FreeBSD problem or HP switch

From: Zhenlei Huang <zlei.huang_at_gmail.com>
Date: Fri, 14 Oct 2022 02:11:06 UTC 
Sorry for missing CC

> Begin forwarded message:
> 
> From: Zhenlei Huang <zlei.huang@gmail.com>
> Subject: Re: is this FreeBSD problem or HP switch
> Date: October 14, 2022 at 10:08:13 AM GMT+8
> To: Jason Bacon <bacon4000@gmail.com>
> 
> 
> 
>> On Oct 14, 2022, at 8:11 AM, Jason Bacon <bacon4000@gmail.com <mailto:bacon4000@gmail.com>> wrote:
>> 
>> On 10/13/22 17:48, Wojciech Puchar wrote:
>>> i have HP-2530-24G switch in home and 3 VLANs.
>>> there was no traffic on 2 of them, one vlan have full bandwitch traffic from computer A to computer B - at 1000Mbit/s
>>> At this time ping from computer C to computer A (computer C have 100Mbit/s card) was random between 1 and 1000ms.
>>> Just limiting artifically speed to 950Mbit/s solved the problem.
>>> Is this because switch behaves that way or can it be a FreeBSD problem (all computers runs FreeBSD)
>> 
>> I saw an issue some years ago where one of my FreeBSD servers was overwhelming a Cisco switch while pushing files out to HTCondor nodes, causing it to drop packets.  Our networks guru confirmed the problem by monitoring the switch.  Since no handshaking was possible, I worked around it by throttling the interface on the FreeBSD box, using ipfw if I recall correctly.
>> 
>> -- 
>> Life is a game.  Play hard.  Play fair.  Have fun.
>> 
>> 
> 
> 
> Modern x86 hardware can easily saturate Gigabit network. Probably it is not the issue of the box, or the OS ( FreeBSD in the context ).
> There's an old post about ICMP packet drops on the HPE community, https://community.hpe.com/t5/aruba-provision-based/hp-procuvre-2530-icmp-packet-lost/td-p/6347333 <https://community.hpe.com/t5/aruba-provision-based/hp-procuvre-2530-icmp-packet-lost/td-p/6347333> . Although I can not conclude it is the problem of switch, but you can try connection the two FreeBSD box directly with crossover ethernet cable and repeat the test.
> 
> Also the statistics reported by switch / OS are extremely useful in production ( when excluding some suspicious objects is not an option ).
> 
> Best regards,
> Zhenlei