서버가 계속 다운되는데 ....

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갑자기 자꾸 다운이 되어 message 로그를 보니 아래와 같은 로그가 있네요
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다운될때 메세지1

Sep 19 18:39:09 localhost named-sdb[3611]: error (network unreachable) resolving 'r.arin.net/AAAA/IN': 2001:500:31::108#53
Sep 19 18:39:09 localhost named-sdb[3611]: error (network unreachable) resolving 't.arin.net/A/IN': 2001:500:31::108#53
Sep 19 18:39:09 localhost named-sdb[3611]: error (network unreachable) resolving 'x.arin.net/AAAA/IN': 2001:500:31::108#53
Sep 19 18:39:09 localhost named-sdb[3611]: error (network unreachable) resolving 't.arin.net/AAAA/IN': 2001:500:31::108#53
Sep 19 18:39:09 localhost named-sdb[3611]: error (network unreachable) resolving 'y.arin.net/AAAA/IN': 2001:500:31::108#53
Sep 19 18:39:10 localhost named-sdb[3611]: error (host unreachable) resolving 'ns2.multacom.com/A/IN': 204.13.152.3#53
Sep 19 19:02:05 localhost named-sdb[3611]: error (network unreachable) resolving '240.69.105.141.in-addr.arpa/PTR/IN': 2001:500:2e::1#53
Sep 19 19:02:05 localhost named-sdb[3611]: error (network unreachable) resolving 'ns1.hostkey.ru/A/IN': 2001:678:17:0:193:232:128:6#53
Sep 19 19:02:05 localhost named-sdb[3611]: error (network unreachable) resolving 'ss.hostkey.ru/A/IN': 2001:678:17:0:193:232:128:6#53
Sep 19 19:02:05 localhost named-sdb[3611]: error (network unreachable) resolving 'ns1.hostkey.ru/AAAA/IN': 2001:678:17:0:193:232:128:6#53
Sep 19 19:02:05 localhost named-sdb[3611]: error (network unreachable) resolving 'ss.hostkey.ru/AAAA/IN': 2001:678:17:0:193:232:128:6#53
Sep 19 19:09:53 localhost kernel: EDAC MC0: UE row 1, channel-a= 0 channel-b= 0 labels "-": (Branch=0 DRAM-Bank=2 RDWR=Read RAS=895 CAS=0 FATAL Err=0x4 (>Tmid Thermal event with intelligent throttling disabled))
Sep 19 19:11:36 localhost named-sdb[3611]: error (network unreachable) resolving 'seonsanms.com/ANY/IN': 2001:503:231d::2:30#53
Sep 19 19:29:29 localhost named-sdb[3611]: error (network unreachable) resolving 'dlv.isc.org/DNSKEY/IN': 2001:500:71::30#53
Sep 19 19:29:30 localhost named-sdb[3611]: error (network unreachable) resolving 'dlv.isc.org/DNSKEY/IN': 2001:500:60::30#53


다운될때 메세지2

Sep 19 22:16:38 localhost named-sdb[2091]: error (network unreachable) resolving 'ns2.lacnic.net/AAAA/IN': 2001:500:13::c7d4:35#53
Sep 19 22:16:39 localhost named-sdb[2091]:   validating @0xb0300ee0: com.cn SOA: no valid signature found
Sep 19 22:16:39 localhost named-sdb[2091]:   validating @0xafbc6518: GICE14DNTMDN31G43AUGVRKTKALVB8QC.com.cn NSEC3: no valid signature found
Sep 19 22:16:39 localhost named-sdb[2091]:   validating @0xafbc6518: MI2OUBFA49Q47917BR600DOL1QGRP79T.com.cn NSEC3: no valid signature found
Sep 19 22:16:39 localhost named-sdb[2091]:   validating @0xafbc6518: UQROTQK62NOIM5U43DMF7AMC8JJFRM7T.com.cn NSEC3: no valid signature found
Sep 19 22:16:39 localhost named-sdb[2091]:   validating @0xb0501540: . SOA: no valid signature found
Sep 19 22:16:39 localhost named-sdb[2091]:   validating @0xb0300468: . NSEC: no valid signature found
Sep 19 22:16:39 localhost named-sdb[2091]:   validating @0xb0300468: loans NSEC: no valid signature found
Sep 19 22:27:19 localhost kernel: EDAC MC0: UE row 3, channel-a= 0 channel-b= 0 labels "-": (Branch=0 DRAM-Bank=1 RDWR=Read RAS=10541 CAS=0 FATAL Err=0x1 (Alert on non-redundant retry or fast reset timeout))
Sep 19 22:34:47 localhost named-sdb[2091]: error (network unreachable) resolving 'wwww.jrdga.info/A/IN': 2001:500:1c::1#53
Sep 19 22:34:49 localhost named-sdb[2091]: error (network unreachable) resolving 'ns1.sdfre.info/AAAA/IN': 2001:500:19::1#53