The MIB defines objects for status and statistics
        information of DNS related operations of
        Global Server Load Balancer(GSLB).  The MIB defines
        objects for global statistical information like DNS
        queries received, DNS responses sent, etc.  Further it
        defines objects for answer, answer group, domain list,
        source address list, proximity rule and DNS rule
        statistics.  It also defines related notifications.
        Acronyms and terminology:
        DNS                   : Domain Name System (RFC1035)
        D-proxy               : Local DNS name server of the
        Answer                : Refers to resources to which the GSLB
                               device resolves DNS requests that it
                               There are three possible types
                               of answers:
                               Virtual IP (VIP) :
                                   Addresses associated with a
                                   server load balancer device,
                                   a web server, a cache, etc.
                               Name Server (NS) : 
                                   Configured DNS name server on the
                                   network that can answer queries
                                   that the GSLB device can not
                               Content Routing Agent (CRA) :
                                   A device which uses a resolution
                                   process called DNS race to send
                                   identical and simultaneous
                                   responses back to a client D-proxy
                                   for proximity determination.
        Answer group          : A logical grouping of answers.  It is a
                               set of virtual IP address (VIP), name
                               server (NS), or content routing agent
                               (CRA) addresses from which an
                               individual answer is selected and used
                               to reply to a content request.  Answers
                               are grouped together as resource pools.
                               The GSLB device, using one of a number
                               of available balance methods, can
                               choose the most appropriate resource
                               to serve each user request from the
                               answers in an answer group.
        Balance method        : A balance method is an algorithm for
                               selecting the best server for
                               replying to a DNS query. 
        Domain list           : A collection of domain names for
                               Internet or intranet resources that
                               have been delegated to the GSLB device
                               for DNS query responses.  Domain lists
                               either contain complete domain names
                               or regular expression that specifies a
                               pattern by which the GSLB device
                               matches incoming DNS requests.
        Source address list   : A collection of IP addresses or address
                               blocks meant to hold information about
                               known D-proxies.  This information is
                               used by the GSLB device while answering
                               DNS queries.
        DNS rule              : A rule which controls the operation of
                               GSLB device.  It identifies the actions
                               to be performed by the GSLB device when
                               it receives a DNS request from a known
                               source (a member of a source address
                               list) for a known domain (a member of
                               a domain list) by specifying which
                               response (answer) is to be given to
                               the requesting D-proxy and how that
                               answer is chosen.
        Proximity             : Refers to the distance or delay, in
                               terms of network topology and not
                               geographic distance, between the
                               requesting client D-proxy and the
                               resources corresponding to that
        Proximity probing     : To respond to DNS requests with the
                               most proximate answers, the GSLB
                               device communicates with a probing
                               device located in each proximity zone
                               to gather round-trip time (RTT) metric
                               information measured between the
                               requesting client D-proxy and the
                               zone.  The GSLB device then directs
                               client requests to an available
                               resource with the lowest RTT value.
        Proximity subsystem   : Component within the GSLB device
                               responsible for proximity
        Clause                : A clause specifies that a particular
                               answer group serve the request and a
                               specific balance method be used to
                               select the best resource from that
                               answer group.
        Boomerang server      : A method of proximity routing used by
                               GSLB device with CRAs.  It is also
                               known as DNS race.
                               The boomerang method is based on the
                               concept that instantaneous proximity
                               can be determined if a CRA within each
                               data center sends a DNS A-record
                               (IP address) at the exact same time
                               to the requesting D-proxy.  This gives
                               all CRAs a chance at resolving a
                               client request and allows for
                               proximity to be determined without
                               probing the client D-proxy.
                               Whichever DNS A-record is received
                               first by the D-proxy is, by default,
                               considered to be the most proximate.
                               For the GSLB device to initiate a DNS
                               race, it needs to establish the
                               following two pieces of information
                               for each CRA:
                               (a) The delay between the GSLB device
                                   and each of the CRAs in each data
                                   center.  With this data, the GSLB
                                   device computes how long to delay
                                   the race from each data center,
                                   so that each CRA starts the race
                               (b) The online status of the CRAs.
                                   With this data, the GSLB device
                                   knows not to forward requests to
                                   any CRA that is not responding.
                               The boomerang server on the GSLB device
                               gathers this information by sending
                               keepalive messages at predetermined
                               intervals.  The boomerang server uses
                               this data, along with the IP addresses
                               of the CRAs, to request the exact start
                               time of the DNS race.  If the CRA
                               response is to be accepted by the
                               D-proxy, each CRA must spoof the IP
                               address of the GSLB device to which
                               the original DNS request was sent.

Imported Objects

CiscoGslbAnswerType, CiscoGslbAnswerStatus, CiscoGslbAnswerAdminState, CiscoGslbBalanceMethodCISCO-GSLB-TC-MIB
InetAddressType, InetAddress, InetAddressPrefixLength, InetAddressDNSINET-ADDRESS-MIB
StorageType, RowStatus, TruthValueSNMPv2-TC
ciscoGslbDnsMIB .
ciscoGslbDnsMIBNotifs .
ciscoGslbDnsEventClause .
ciscoGslbAnswerEventStatusChange .
ciscoGslbDnsMIBObjects .
cgdNotifControl .
cgdDnsClauseNotifEnable .
cgdDnsAnswerNotifEnable .
cgdNotifObjects .
cgdAnswerPrevStatus .
cgdGlobal .
cgdTotalDomains .
cgdTotalDomainLists .
cgdTotalSourceAddresses .
cgdTotalSourceAddressLists .
cgdTotalAnswers .
cgdTotalAnswerGroups .
cgdTotalRules .
cgdAnsTrapRateLimit .
cgdDnsClauseTrapRateLimit .
cgdGlobalStats .
cgdDnsRcvdQueries .
cgdDnsQueryRateCurrent .
cgdDnsQueryRatePeak .
cgdDnsUdpSrcPortErrs .
cgdDnsTcpSrcPortErrs .
cgdDnsPollSockErrs .
cgdDroppedAnsNotifs .
cgdDroppedDnsClauseNotifs .
cgdDnsRcvdHostAddrQueries .
cgdDnsUnmatchedQueries .
cgdDnsDroppedQueries .
cgdNSFwdSentQueries .
cgdNSFwdRcvdResps .
cgdBoomServSentReqs .
cgdProxLkupSentReqs .
cgdProxLkupRcvdResps .
cgdAnswer .
cgdAnswerGroupTable .
cgdAnswerGroupEntry .
cgdAnswerGroupName .
cgdAnswerGroupType .
cgdAnswerGroupHits .
cgdAnswerGroupStorageType .
cgdAnswerGroupRowStatus .
cgdAnswerTable .
cgdAnswerEntry .
cgdAnswerId .
cgdAnswerRate1Min .
cgdAnswerRate5Min .
cgdAnswerRate30Min .
cgdAnswerRate4Hr .
cgdAnswerStorageType .
cgdAnswerRowStatus .
cgdAnswerType .
cgdAnswerAddressType .
cgdAnswerAddress .
cgdAnswerName .
cgdAnswerGrpName .
cgdAnswerAdminState .
cgdAnswerStatus .
cgdAnswerHits .
cgdDomain .
cgdDomainListTable .
cgdDomainListEntry .
cgdDomainListName .
cgdDomainListHits .
cgdDomainListStorageType .
cgdDomainListRowStatus .
cgdDomainTable .
cgdDomainEntry .
cgdDomainId .
cgdDomainRowStatus .
cgdDomainName .
cgdDomainList .
cgdDomainHits .
cgdDomainRate1Min .
cgdDomainRate5Min .
cgdDomainRate30Min .
cgdDomainRate4Hr .
cgdDomainStorageType .
cgdSourceAdd .
cgdSourceAddressListTable .
cgdSourceAddressListEntry .
cgdSourceAddressListName .
cgdSourceAddressListHits .
cgdSourceAddressListStorageType .
cgdSourceAddressListRowStatus .
cgdSourceAddressTable .
cgdSourceAddressEntry .
cgdSourceAddressId .
cgdSourceAddressRate4Hr .
cgdSourceAddressStorageType .
cgdSourceAddressRowStatus .
cgdSourceAddressAddressType .
cgdSourceAddressAddress .
cgdSourceAddressPrefixLength .
cgdSourceAddressList .
cgdSourceAddressHits .
cgdSourceAddressRate1Min .
cgdSourceAddressRate5Min .
cgdSourceAddressRate30Min .
cgdDnsRule .
cgdClauseTable .
cgdClauseEntry .
cgdClauseId .
cgdClauseAnsGrpName .
cgdClauseBalanceMethod .
cgdClauseHits .
cgdClauseStorageType .
cgdClauseRowStatus .
cgdDnsRuleTable .
cgdDnsRuleEntry .
cgdDnsRuleName .
cgdDnsRuleRowStatus .
cgdFirstClauseId .
cgdSecondClauseId .
cgdThirdClauseId .
cgdSourceAddList .
cgdDNSRuleDomainList .
cgdDnsRuleHits .
cgdDnsRuleSuccesses .
cgdDnsRuleStorageType .
ciscoGslbDnsMIBConform .
ciscoGslbDnsMIBCompliances .
ciscoGslbDnsMIBGroups .