DeclarationsDeclarations
FunctionsFunctions
OperatorsOperators
StatementsStatements
SubroutinesSubroutines
TypesTypes
VariablesVariables
- Date and timeDate and time
- ESIESI
- GeolocationGeolocation
- Math constants limitsMath constants limits
- MiscellaneousMiscellaneous
  - backend.conn.is_tlsbackend.conn.is_tls
  - backend.conn.tls_protocolbackend.conn.tls_protocol
  - backend.socket.congestion_algorithmbackend.socket.congestion_algorithm
  - backend.socket.cwndbackend.socket.cwnd
  - backend.{NAME}.connections_openbackend.{NAME}.connections_open
  - backend.{NAME}.connections_usedbackend.{NAME}.connections_used
  - backend.{NAME}.healthybackend.{NAME}.healthy
  - bereq.between_bytes_timeoutbereq.between_bytes_timeout
  - bereq.connect_timeoutbereq.connect_timeout
  - bereq.first_byte_timeoutbereq.first_byte_timeout
  - bereq.http.{NAME}bereq.http.{NAME}
  - bereq.is_clusteringbereq.is_clustering
  - bereq.methodbereq.method
  - bereq.protobereq.proto
  - bereq.requestbereq.request
  - bereq.urlbereq.url
  - bereq.url.basenamebereq.url.basename
  - bereq.url.dirnamebereq.url.dirname
  - bereq.url.extbereq.url.ext
  - bereq.url.pathbereq.url.path
  - bereq.url.qsbereq.url.qs
  - beresp.backend.alternate_ipsberesp.backend.alternate_ips
  - beresp.backend.ipberesp.backend.ip
  - beresp.backend.nameberesp.backend.name
  - beresp.backend.portberesp.backend.port
  - beresp.backend.requestsberesp.backend.requests
  - beresp.backend.src_ipberesp.backend.src_ip
  - beresp.brotliberesp.brotli
  - beresp.cacheableberesp.cacheable
  - beresp.do_streamberesp.do_stream
  - beresp.graceberesp.grace
  - beresp.gzipberesp.gzip
  - beresp.handshake_time_to_origin_msberesp.handshake_time_to_origin_ms
  - beresp.hipaaberesp.hipaa
  - beresp.http.{NAME}beresp.http.{NAME}
  - beresp.pciberesp.pci
  - beresp.protoberesp.proto
  - beresp.responseberesp.response
  - beresp.saintmodeberesp.saintmode
  - beresp.stale_if_errorberesp.stale_if_error
  - beresp.stale_while_revalidateberesp.stale_while_revalidate
  - beresp.statusberesp.status
  - beresp.ttlberesp.ttl
  - beresp.used_alternate_path_to_originberesp.used_alternate_path_to_origin
  - client.identityclient.identity
  - client.ipclient.ip
  - client.portclient.port
  - client.requestsclient.requests
  - client.sess_timeoutclient.sess_timeout
  - client.socket.congestion_algorithmclient.socket.congestion_algorithm
  - client.socket.cwndclient.socket.cwnd
  - client.socket.nexthopclient.socket.nexthop
  - client.socket.paceclient.socket.pace
  - client.socket.plossclient.socket.ploss
  - client.socket.tcp_infoclient.socket.tcp_info
  - director.{NAME}.healthydirector.{NAME}.healthy
  - fastly.errorfastly.error
  - fastly.ff.visits_this_pop_this_servicefastly.ff.visits_this_pop_this_service
  - fastly.ff.visits_this_servicefastly.ff.visits_this_service
  - fastly_info.edge.is_tlsfastly_info.edge.is_tls
  - fastly_info.statefastly_info.state
  - obj.ageobj.age
  - obj.cacheableobj.cacheable
  - obj.enteredobj.entered
  - obj.graceobj.grace
  - obj.hitsobj.hits
  - obj.http.{NAME}obj.http.{NAME}
  - obj.is_pciobj.is_pci
  - obj.lastuseobj.lastuse
  - obj.protoobj.proto
  - obj.responseobj.response
  - obj.stale_if_errorobj.stale_if_error
  - obj.stale_while_revalidateobj.stale_while_revalidate
  - obj.statusobj.status
  - obj.ttlobj.ttl
  - re.group.{N}re.group.{N}
  - req.backendreq.backend
  - req.backend.healthyreq.backend.healthy
  - req.backend.is_clusterreq.backend.is_cluster
  - req.backend.is_originreq.backend.is_origin
  - req.backend.is_shieldreq.backend.is_shield
  - req.bodyreq.body
  - req.body.base64req.body.base64
  - req.digestreq.digest
  - req.digest.ratioreq.digest.ratio
  - req.enable_range_on_passreq.enable_range_on_pass
  - req.enable_segmented_cachingreq.enable_segmented_caching
  - req.gracereq.grace
  - req.hashreq.hash
  - req.hash_always_missreq.hash_always_miss
  - req.hash_ignore_busyreq.hash_ignore_busy
  - req.http.{NAME}req.http.{NAME}
  - req.is_background_fetchreq.is_background_fetch
  - req.is_clusteringreq.is_clustering
  - req.is_ipv6req.is_ipv6
  - req.is_purgereq.is_purge
  - req.is_sslreq.is_ssl
  - req.max_stale_if_errorreq.max_stale_if_error
  - req.max_stale_while_revalidatereq.max_stale_while_revalidate
  - req.methodreq.method
  - req.postbodyreq.postbody
  - req.protoreq.proto
  - req.protocolreq.protocol
  - req.requestreq.request
  - req.restartsreq.restarts
  - req.service_idreq.service_id
  - req.urlreq.url
  - req.url.basenamereq.url.basename
  - req.url.dirnamereq.url.dirname
  - req.url.extreq.url.ext
  - req.url.pathreq.url.path
  - req.url.qsreq.url.qs
  - req.vclreq.vcl
  - req.vcl.generationreq.vcl.generation
  - req.vcl.md5req.vcl.md5
  - req.vcl.versionreq.vcl.version
  - req.xidreq.xid
  - resp.completedresp.completed
  - resp.http.{NAME}resp.http.{NAME}
  - resp.is_locally_generatedresp.is_locally_generated
  - resp.protoresp.proto
  - resp.responseresp.response
  - resp.staleresp.stale
  - resp.stale.is_errorresp.stale.is_error
  - resp.stale.is_revalidatingresp.stale.is_revalidating
  - resp.statusresp.status
  - stale.existsstale.exists
  - workspace.bytes_freeworkspace.bytes_free
  - workspace.bytes_totalworkspace.bytes_total
  - workspace.overflowedworkspace.overflowed
- Segmented cachingSegmented caching
- ServerServer
- SizeSize
- TCP infoTCP info
- TLS and HTTPTLS and HTTP

backend.{NAME}.connections_used

INTEGER, read-only.

Number of connections currently in use for a particular backend.

User contributed notes

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