Infrastructure Software

Hi
Today , I could not log into one of the server(A) in my working place using Putty SSH as root user. After I key in the username it prompted me "Server unexpectedly closed network connection". My putty session went into inactive session.I also tried others user login and encounter the same error.
Putty.log
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Incoming packet #0x5, type 53 / 0x35 (SSH2_MSG_USERAUTH_BANNER)
00000000 00 00 02 22 0a 7c 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d ...".|----------
00000010 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d ----------------
00000020 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d ----------------
00000030 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d ----------------
00000040 2d 2d 2d 2d 2d 2d 2d 7c 0a 7c 20 55 73 65 20 6f -------|.| Use o
00000050 66 20 74 68 69 73 20 70 72 69 76 61 74 65 20 63 f this private c
00000060 6f 6d 70 75 74 65 72 20 73 79 73 74 65 6d 20 69 omputer system i
00000070 73 20 79 6f 75 72 20 63 6f 6e 73 65 6e 74 20 74 s your consent t
00000080 6f 20 62 65 69 6e 67 20 20 20 20 7c 0a 7c 20 6d o being |.| m
00000090 6f 6e 69 74 6f 72 65 64 20 61 6e 64 20 72 65 63 onitored and rec
000000a0 6f 72 64 65 64 2e 20 55 6e 61 75 74 68 6f 72 69 orded. Unauthori
000000b0 7a 65 64 20 75 73 65 20 69 73 20 70 72 6f 68 69 zed use is prohi
000000c0 62 69 74 65 64 2e 20 20 20 20 20 20 20 20 20 7c bited. |
000000d0 0a 7c 20 20 20 20 20 20 20 20 20 20 20 20 20 20 .|
000000e0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20
000000f0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20
00000100 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20
00000110 20 20 20 7c 0a 7c 20 57 65 20 72 65 73 65 72 76 |.| We reserv
00000120 65 20 74 68 65 20 72 69 67 68 74 20 74 6f 20 73 e the right to s
00000130 65 65 6b 20 61 6c 6c 20 72 65 6d 65 64 69 65 73 eek all remedies
00000140 20 66 6f 72 20 75 6e 61 75 74 68 6f 72 69 7a 65 for unauthorize
00000150 64 20 75 73 65 2e 20 7c 0a 7c 20 45 76 69 64 65 d use. |.| Evide
00000160 6e 63 65 20 6f 66 20 73 75 73 70 65 63 74 65 64 nce of suspected
00000170 20 69 6c 6c 65 67 61 6c 20 75 73 65 20 6d 61 79 illegal use may
00000180 20 62 65 20 67 69 76 65 6e 20 74 6f 20 6c 61 77 be given to law
00000190 20 20 20 20 20 20 20 20 20 20 20 7c 0a 7c 20 65 |.| e
000001a0 6e 66 6f 72 63 65 6d 65 6e 74 2e 20 20 20 20 20 nforcement.
000001b0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20
000001c0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20
000001d0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 7c |
000001e0 0a 7c 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d .|--------------
000001f0 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d ----------------
00000200 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d ----------------
00000210 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d ----------------
00000220 2d 2d 2d 7c 0a 0a 00 00 00 00 ---|......
Incoming packet #0x6, type 51 / 0x33 (SSH2_MSG_USERAUTH_FAILURE)
00000000 00 00 00 44 67 73 73 61 70 69 2d 6b 65 79 65 78 ...Dgssapi-keyex
00000010 2c 67 73 73 61 70 69 2d 77 69 74 68 2d 6d 69 63 ,gssapi-with-mic
00000020 2c 70 75 62 6c 69 63 6b 65 79 2c 70 61 73 73 77 ,publickey,passw
00000030 6f 72 64 2c 6b 65 79 62 6f 61 72 64 2d 69 6e 74 ord,keyboard-int
00000040 65 72 61 63 74 69 76 65 00 eractive.
Outgoing packet #0x6, type 50 / 0x32 (SSH2_MSG_USERAUTH_REQUEST)
00000000 00 00 00 04 72 6f 6f 74 00 00 00 0e 73 73 68 2d ....root....ssh-
00000010 63 6f 6e 6e 65 63 74 69 6f 6e 00 00 00 0f 67 73 connection....gs
00000020 73 61 70 69 2d 77 69 74 68 2d 6d 69 63 00 00 00 sapi-with-mic...
00000030 01 00 00 00 0b 06 09 2a 86 48 86 f7 12 01 02 02 .......*.H......
Outgoing raw data
00000000 ce d6 7d 07 47 80 8b ba 42 04 27 29 39 0e 55 33 ..}.G...B.')9.U3
00000010 75 8b a7 39 6c 47 b1 72 99 83 38 3b 85 60 04 b0 u..9lG.r..8;.`..
00000020 59 75 e0 dd bd 3b 75 ee 94 1a 77 89 5e f4 ec 4c Yu...;u...w.^..L
00000030 7e 39 6a 37 61 df e9 0d fd b4 a0 9a 94 f1 24 31 ~9j7a.........$1
00000040 0a cf e0 3f 96 86 7b e3 5d eb 2d f2 c0 40 4a 9f ...?..{.].-..@J.
00000050 ac ea 15 c2 06 2c 7d f1 f4 fd f6 22 e8 82 73 cb .....,}...."..s.
00000060 31 81 bb 8f 1...
Incoming raw data
00000000 fc 69 70 ae d5 e2 eb 03 a9 51 03 af c7 6e 7b 77 .ip......Q...n{w
00000010 9a 19 6c 77 c9 4b 52 44 d2 8b ce fd 9b 6d 20 54 ..lw.KRD.....m T
00000020 c0 e6 03 b7 f0 e1 6f 7f 02 83 a4 08 a5 d3 9d ad ......o.........
00000030 9a 11 e3 48 ...H
Incoming packet #0x7, type 60 / 0x3c (SSH2_MSG_USERAUTH_GSSAPI_RESPONSE)
00000000 00 00 00 0b 06 09 2a 86 48 86 f7 12 01 02 02 ......*.H......
Event Log: GSSAPI authentication initialisation failed
Event Log: The target was not recognized.
Outgoing packet #0x7, type 50 / 0x32 (SSH2_MSG_USERAUTH_REQUEST)
00000000 00 00 00 04 72 6f 6f 74 00 00 00 0e 73 73 68 2d ....root....ssh-
00000010 63 6f 6e 6e 65 63 74 69 6f 6e 00 00 00 14 6b 65 connection....ke
00000020 79 62 6f 61 72 64 2d 69 6e 74 65 72 61 63 74 69 yboard-interacti
00000030 76 65 00 00 00 00 00 00 00 00 ve........
Outgoing raw data
00000000 f0 fd 23 47 5c ba 94 39 e1 bf 0f 68 a4 ed e0 ec ..#G\..9...h....
00000010 64 47 53 bf ad 75 fb f7 90 12 2f e6 27 55 80 d1 dGS..u..../.'U..
00000020 a4 b4 ac 43 ed 59 39 f6 2f ff 58 26 d0 c7 e0 c7 ...C.Y9./.X&....
00000030 88 49 3d 15 df 85 be d8 af 1a 6d cb e1 a1 c7 38 .I=.......m....8
00000040 6d 37 9d 77 f4 ee 13 56 07 27 ce 36 ea 12 93 79 m7.w...V.'.6...y
00000050 78 d9 bb e0 e6 46 56 79 55 31 d7 aa 13 f8 0b 5f x....FVyU1....._
00000060 3f 45 7e 4d ?E~M
Event Log: Server unexpectedly closed network connection
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Since server(A) is a non global zone for server(B), I log into server(B) root and zlogin server(A). It return me,
========================================================================================================
root@server(B) # zlogin server(A)
[Connected to zone 'server(A)' pts/17]

[Connection to zone 'server(A)' pts/17 closed]
root@server(B) #
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Funny thing is that I can log in using zlogin -S server(A) and zlogin -C server(A) without problems.
I could also do a ping to server(A).
I also had check weather server(A) is up and running.
root@server(B) # /usr/sbin/zoneadm list -vi
ID NAME STATUS PATH BRAND IP
0 global running / native shared
1 server(A) running /zones/server(A) native excl

Its my first time encountering this error. I hope someone could give me advice or guide.

Thank You