Um roteador Cisco 2821 rodando IOS 12.4(15)T1 a 450 dias precisou ser parado para troca do fan de exaustão. Ao religarmos nos deparamos com o erro abaixo:

System Bootstrap, Version 12.4(1r) [hqluong 1r], RELEASE SOFTWARE (fc1)<br /> Copyright (c) 2005 by cisco Systems, Inc.<br /> Initializing memory for ECC<br /> ....<br /> Bad RAM at location 0xA0000B14: wrote 0xA0000B14, read 0xA07E0B14<br />

Esse roteador possui 2 pentes de 512 MB. Tentamos inverter as memórias de slot e erro mudou para:

`System Bootstrap, Version 12.4(1r) [hqluong 1r], RELEASE SOFTWARE (fc1)
Copyright (c) 2005 by cisco Systems, Inc.</p>

Initializing memory for ECC
....

Retrieving primary rommon variables...
c2821 processor with 1048576 Kbytes of main memory
Main memory is configured to 64 bit mode with ECC enabled

Readonly ROMMON initialized
program load complete, entry point: 0x8000f000, size: 0xc940
program load complete, entry point: 0x8000f000, size: 0xc940

program load complete, entry point: 0x8000f000, size: 0x323a448
Self decompressing the image : ################################################################################################################################################################################################################################################################################################ [OK]

Smart Init is enabled
smart init is sizing iomem
ID MEMORY_REQ TYPE
0003E8 0X003DA000 C2821 Mainboard
00053A 0X000C2800 1-port FE HWIC
0X00264050 Onboard VPN
0X000021B8 Onboard USB
0X002C29F0 public buffer pools
0X00211000 public particle pools
TOTAL: 0X00BD63F8

If any of the above Memory Requirements are
"UNKNOWN", you may be using an unsupported
configuration or there is a software problem and
system operation may be compromised.
Rounded IOMEM up to: 12Mb.
Using 1 percent iomem. [12Mb/1024Mb]
SDRAM ECC Error,
err addr - 0x5D090000, err data_l 0x00000E00,err data_h 0x00000000,
rcv ecc - 0x00000000, calc ecc 0xEC000000, err cnt 0xB97D0A00
r0 = FFFFFFFF r1 = FFFFFFFF r2 = 0 r3 = 462C0000 r4 = 0
r5 = 38 r6 = 0 r7 = 0 r8 = 0 r9 = 20
r10 = FFFFFFFF r11 = FFFDFFFF r12 = 0 r13 = 0 r14 = 0
r15 = 5 r16 = 0 r17 = C100 r18 = 0 r19 = 3400C101
r20 = 0 r21 = 40086828 r22 = FFFFFFFF r23 = FFFF00FF r24 = 0
r25 = 8000000 r26 = 0 r27 = 0 r28 = 0 r29 = 0
r30 = 0 r31 = 8000000 r32 = FFFFFFFF r33 = FFFFFFFF r34 = FFFFFFFF
r35 = FFFFFFFF r36 = FFFFFFFF r37 = FFFFFFFF r38 = FFFFFFFF r39 = FFFFFFFF
r40 = FFFFFFFF r41 = FFFFFFFF r42 = FFFFFFFF r43 = FFFFFFFF r44 = FFFFFFFF
r45 = FFFFFFFF r46 = FFFFFFFF r47 = FFFFFFFF r48 = 0 r49 = 0
r50 = 0 r51 = 0 r52 = 0 r53 = 3040A801 r54 = FFFFFFFF
r55 = A000F000 r56 = FFFFFFFF r57 = FFFFFFFF r58 = FFFFFFFF r59 = 8000EE20
r60 = FFFFFFFF r61 = FFFFFFFF r62 = 0 r63 = 4009F3C8
sreg = 3400C103 mdlo_hi = 0 mdlo = 3E8
mdhi_hi = 0 mdhi = 0 badvaddr_hi = FFFFFFFF
badvaddr = FFFFFFFF cause = FFFFFFFF epc_hi = 0
epc = 40085610 err_epc_hi = FFFFFFFF err_epc = FFFFFFFF

%ERR-1-FATAL: Fatal error interrupt, reloading
err_stat=0x0
` Resumindo, o problema estava na memória do slot2. Trocamos a mesma e o boot foi concluído com sucesso. Mesmo usando pulseiras anti-estática e racks aterrados é importante ter o máximo de atenção com a eletroestática quando for necessária manutenções internas de roteadores/switches.