a new one - if "re0" stopped responding

22_oct_22_sat 20.55.utc



howdy , folks ---

regarding the problem , which i describe here_in .
   i am convinced that it results from some_thing , which i did ;
   but , what_ever the cause ,
   it was done w/ neither knowledge nor intent , before_hand .
i wonder if the cause is some_thing non_intuitive .



while preparing my 22_oct_20_thu response to david , on "-questions" ,
   regarding my isp's dhcp addresses
   [ there is much info in that post , which i will not repeat , here ] ,
   i booted [ on 22_oct_19_wed ] natalie_11.3 , 192.168.100.201 ,
   for the purpose of seeking some information .

usually , i ssh from catherine_11.4 ; but , ssh "timed out" .
i tried ping ; there was no response .
i tried this , both ,
   as "natalie" , by name , and
   as "192.168.100.201" , by address .

well , to get the job done , i got what i needed from the console ,
   with the intent of researching this behavior , later .

yesterday , 22_oct_21_fri , "later" arrived .
i tried a number of things ; here are some observations .

move the rj45 plug
   from the re0 socket [ addr .201 ]
   to   the em0 socket [ addr .202 ] .
ping and ssh work correctly .
move the rj45 back to re0 ; no response and "timed out" .

next , while doing this several times ,
   after each move , i invoked ifconfig .
both re0 and em0 report "UP" and "RUNNING" and
   their mac_ and inet_addresses are correct .
after each move , "status" and "media" exchange places ,
   between
     "no carrier" and "Ethernet autoselect (none)"
   and
     "active"     and "Ethernet autoselect (1000baseT <full-duplex>)" .
the boot messages look ok .
the rear_panel steady/flashing leds behave as expected .
i even tried moving the rj45 , for natalie's cable ,
   to a different port on the network_switch .

for a_while , i ruminated .

then , i concluded that "this must be a hardware problem" .

[ i digress briefly .
   there is a widely_known "myth" [ is it , really ? ] that
     electronics_hardware contains a "crisis_detector" circuit .
   it identifies when the user is in
     a higher_than_usual state_of_anxiety .
   then , it implements some "worst_place" , "worst_time" failure .
   for em0 , which is a plug_in card [ i have several spares ] ,
     this is a 5_minute swap .
   because my difficulty is with re0 and my isp ,
     then , necessarily , the problem is with re0 .
   re0 is built_in , on the mobo .
   i have spare parts , for every_thing ;
     but , swapping moboes is not a 5_minute job .
]

so , earlier today , 22_oct_22_sat , i assembled
   a new mobo , a new cpu/fan and 2 new dram sticks .
the case , psu and the em0_nic are the same ;
   so is the only hd [ w/ 11.3 amd64 on it ] .



HORRORS !!!

re0 does not respond on this mobo , either .
ifconfig and all of the other tests give the same results .

i have spent more_than_a_few minutes , today ,
   being slack_jawed , while staring at screens .

every_thing worked fine , on 22_sep_25_sun ,
   when i shut_down natalie_11.3 ;
   the non_response began immediately , with the boot of 22_oct_19_wed
   [ i had to "catch_up" on other things , in the mean_time ] .



i am convinced that i changed some_thing , in_advertently ;
   how_ever , i have no idea what it could be .
again , i wonder if this could be some_thing , which is non_intuitive .

at_least , because i intend to build 3 boxen ,
   assembling today's mobo was not a waste of time ,
   as the original mobo is still good , probably ;
   i was just early .



update 20.15.utc

i just had one_more idea of some_thing to try .

shut_down , swap_in the natalie/natasha_12.3 hd and boot .

EUREKA !!!

the re0 if --works-- , on natalie , using address .201 ;
   i pinged and i sshed .

--now-- , i --know-- that this is --not-- a hardware problem .

there_fore , the severity level of this problem has been down_graded
   from "crisis"
   [ because i can not solve the dhcp_problem w/o 2 ifs ]
   to "very_important"
   [ because , if i did what_ever i did once , in_advertently ,
       then , easily , i could do it again , in_advertently
   ] .

if i can learn the cause of this behavior ,
   then , if it happens again , i will have some idea of what to do .
so , posting this question remains legitimate .



any thoughts , any_one ?



tia

rob