Per-virtual-system concurrent connection limit nearing-f5-False

error
health-checks
false
f5
Per-virtual-system concurrent connection limit nearing-f5-False
0

#1

Per-virtual-system concurrent connection limit nearing-f5-False

Vendor: f5

OS: False

Description:
indeni will trigger an issue the number of connections in a VS is too high.

Remediation Steps:
Review why this may be happening and consider moving some of the traffic between VS’s or devices.

How does this work?
This alert logs into the F5 unit through SSH and extracts the current number of concurrent connections via TMSH.

Why is this important?
Concurrent connections is important to track and graph for troubleshooting purposes. While F5 units do not have a static upper limit in terms of number of connections it is still is regulated by memory usage.

Without Indeni how would you find this?
This metric is available by logging into the unit through SSH, entering TMSH and issuing the command “show sys performance connections”.

f5-tmsh-show-sys-performance-connections

 #! META
name: f5-tmsh-show-sys-performance-connections
description: Get system wide concurrent connection statistics
type: monitoring
monitoring_interval: 1 minute
requires:
    vendor: "f5"
    product: "load-balancer"
    linux-based: "true"
    shell: "bash"

#! COMMENTS
concurrent-connections:
    why: |
        Concurrent connections is important to track and graph for troubleshooting purposes. While F5 units do not have a static upper limit in terms of number of connections it is still is regulated by memory usage. 
    how: |
        This alert logs into the F5 unit through SSH and extracts the current number of concurrent connections via TMSH.
    without-indeni: |
        This metric is available by logging into the unit through SSH, entering TMSH and issuing the command "show sys performance connections".
    can-with-snmp: false
    can-with-syslog: false
#! REMOTE::SSH
tmsh -q show sys performance connections raw
 
#! PARSER::AWK

BEGIN{
    connsPerSec = 0
}

/^Connections/{
    writeDoubleMetric("concurrent-connections", null, "number", 60, $2)
}

/^(Client|Server) Connections/{
    connsPerSec += $3
}

END{
    writeDoubleMetric("connections-per-second", null, "number", 60, connsPerSec)
}

concurrent_connection_limit_vsx

package com.indeni.server.rules.library

import com.indeni.ruleengine.expressions.OptionalExpression
import com.indeni.ruleengine.expressions.conditions.GreaterThanOrEqual
import com.indeni.ruleengine.expressions.core.{StatusTreeExpression, _}
import com.indeni.ruleengine.expressions.data.{SelectTagsExpression, SelectTimeSeriesExpression, TimeSeriesExpression}
import com.indeni.ruleengine.expressions.math.{DivExpression, TimesExpression}
import com.indeni.server.common.data.conditions.True
import com.indeni.server.params.ParameterDefinition
import com.indeni.server.params.ParameterDefinition.UIType
import com.indeni.server.rules._
import com.indeni.server.rules.library.ConcurrentConnectionsUsageVsxRule.NAME
import com.indeni.server.rules.library.core.PerDeviceRule
import com.indeni.server.sensor.models.managementprocess.alerts.dto.AlertSeverity

case class ConcurrentConnectionsUsageVsxRule() extends PerDeviceRule with RuleHelper {

  private[library] val highThresholdParameterName = "High_Threshold_of_Connection_usage"
  private val highThresholdParameter = new ParameterDefinition(highThresholdParameterName,
    "",
    "High Threshold of Concurrent Connection Usage",
    "What is the threshold for the concurrent connection usage for which once it is crossed an issue will be triggered.",
    UIType.DOUBLE,
    80.0)

  override val metadata: RuleMetadata = RuleMetadata.builder(NAME, "All Devices: Per-virtual-system concurrent connection limit nearing",
    "indeni will trigger an issue the number of connections in a VS is too high.", AlertSeverity.ERROR).configParameter(highThresholdParameter).build()

  override def expressionTree(context: RuleContext): StatusTreeExpression = {
    val actualValue = TimeSeriesExpression[Double]("concurrent-connections").last
    val threshold: OptionalExpression[Double] = getParameterDouble(highThresholdParameter)
    val limit = TimeSeriesExpression[Double]("concurrent-connections-limit").last

    StatusTreeExpression(
      // Which objects to pull (normally, devices)
      SelectTagsExpression(context.metaDao, Set(DeviceKey), True),

      // What constitutes an issue
        StatusTreeExpression(

          // The additional tags we care about (we'll be including this in alert data)
          SelectTagsExpression(context.tsDao, Set("vs.id","vs.name"), True),

            StatusTreeExpression(
              // The time-series we check the test condition against:
              SelectTimeSeriesExpression[Double](context.tsDao, Set("concurrent-connections", "concurrent-connections-limit"), denseOnly = false),

              // The condition which, if true, we have an issue. Checked against the time-series we've collected
              GreaterThanOrEqual(
                actualValue,
                TimesExpression(limit, DivExpression(threshold, ConstantExpression(Some(100.0)))))

              // The Alert Item to add for this specific item
            ).withSecondaryInfo(
                scopableStringFormatExpression("${scope(\"vs.name\")} (${scope(\"vs.id\")})"),
                scopableStringFormatExpression("Usage of %.0f (vs limit of %.0f) is above the threshold of %.0f%%.", actualValue, limit, threshold),
                title = "Affected VS's"
            ).asCondition()
        ).withoutInfo().asCondition()
    ).withRootInfo(
        getHeadline(),
        ConstantExpression("Some VS's have a high number of concurrent connections.\n\nThis issue was added per the request of <a target=\"_blank\" href=\"http://il.linkedin.com/in/motisagey\">Moti Sagey</a>."),
        ConditionalRemediationSteps("Review why this may be happening and consider moving some of the traffic between VS's or devices.",
          ConditionalRemediationSteps.VENDOR_CP -> "Consider enabling aggressive aging if it is not yet enabled: https://sc1.checkpoint.com/documents/R76/CP_R76_IPS_AdminGuide/12857.htm#o12861",
          ConditionalRemediationSteps.VENDOR_PANOS -> "Compare the products and the maximum sessions allowed: https://www.paloaltonetworks.com/products/product-selection"
      )
    )
  }
}

object ConcurrentConnectionsUsageVsxRule {

  /* --- Constants --- */

  private[library] val NAME = "concurrent_connection_limit_vsx"
}