When a link LED does not light (indicating loss of link between two devices), the most common reason is a failure of port auto-negotiation between the connecting ports. If a link LED fails to light when you connect the switch to a port on another device, do the following:
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Ensure that the switch port and the port on the attached end-node are both set to
Automode. -
If the attached end-node does not have an
Automode setting, you must manually configure the switch port to the same setting as the end-node port. See Port Status and Configuration.
The ping test and the link test are point-to-point tests between your switch and another IEEE 802.3-compliant device on your network. These tests can tell you whether the switch is communicating properly with another device.
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NOTE: To respond to a ping test or a link test, the device you are trying to reach must be IEEE 802.3-compliant. |
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A test of the path between the switch and another device on the same or another IP network that can respond to IP packets (ICMP Echo Requests). To use the ping (or traceroute) command with host names or fully qualified domain names, see DNS resolver.
A test of the connection between the switch and a designated network device on the same LAN (or VLAN, if configured). During the link test, IEEE 802.2 test packets are sent to the designated network device in the same VLAN or broadcast domain. The remote device must be able to respond with an 802.2 Test Response Packet.
To start a ping or link test in the WebAgent:
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In the navigation pane, click Troubleshooting.
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Click Ping/Link Test.
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Click Start.
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To halt a link or ping test before it concludes, click Stop.
For an Example: of the text screens, see Ping test and link test screen on the WebAgent.
Destination IP Address is the network address of the target, or destination, device to which you want to test a connection with the switch. An IP address is in the X.X.X.X format where X is a decimal number between 0 and 255.
Number of Packets to Send is the number of times you want the switch to attempt to test a connection.
Timeout in Seconds is the number of seconds to allow per attempt to test a connection before determining that the current attempt has failed.
The ping test uses ICMP echo requests and ICMP echo replies to determine if another device is alive. It also measures the amount of time it takes to receive a reply from the specified destination. The ping command has several extended commands that allow advanced checking of destination availability.
Syntax:
ping6<ipv6-address | hostname> [repetitions <1-10000>] [timeout <1-60>] [source < ip-address | vlan-id | loopback <0-7>> ] [data-size <0-65471>] [data-fill <0-1024>]Sends ICMP echo requests to determine if another device is alive.
<
ip-address|hostname>Target IP address or hostname of the destination node being pinged
repetitions <1-10000>Number of ping packets sent to the destination address.
Default: 1
Timeout interval in seconds; the ECHO REPLY must be received before this time interval expires for the ping to be successful.
Default: 5
source<ip-addr|vid|loopback <0-7>>Source IP address, VLAN ID, or loopback address used for the ping.
The source IP address must be owned by the router.
If a VLAN is specified, the IP address associated with the specified VLAN is used.
data-size <0-65471>Size of packet sent.
Default: 0 (zero)
data-fill <0-1024>The data pattern in the packet.
Default: Zero length string
Ping tests
HP Switch# ping 10.10.10.10 10.10.10.10 is alive, time = 15 ms HP Switch# ping 10.10.10.10 repetitions 3 10.10.10.10 is alive, iteration 1, time = 15 ms 10.10.10.10 is alive, iteration 1, time = 15 ms 10.10.10.10 is alive, iteration 1, time = 15 ms HP Switch# ping 10.10.10.10 timeout 2 10.10.10.10 is alive, time = 10 ms HP Switch# ping 10.11.12.13 The destination address is unreachable.
To halt a ping test before it concludes, press [Ctrl] [C].
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NOTE: To use the |
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The traceroute command enables you to trace the route from the switch to a host address.
This command outputs information for each (router) hop between the switch and the destination address. Note that every time you execute traceroute, it uses the same default settings unless you specify otherwise for that instance of the command.
Syntax:
Lists the IP address or hostname of each hop in the route, plus the time in microseconds for the
traceroutepacket reply to the switch for each hop.
<
ip-address|hostname>The IP address or hostname of the device to which to send the traceroute.
[
minttl <]1-255>For the current instance of
traceroute, changes the minimum number of hops allowed for each probe packet sent along the route.
If
minttlis greater than the actual number of hops, the output includes only the hops at and above theminttlthreshold. (The hops below the threshold are not listed.)If
minttlmatches the actual number of hops, only that hop is shown in the output.If
minttlis less than the actual number of hops, all hops are listed.For any instance of
traceroute, if you want aminttlvalue other than the default, you must specify that value.(Default: 1)
[
maxttl <]1-255>For the current instance of
traceroute, changes the maximum number of hops allowed for each probe packet sent along the route.If the destination address is further from the switch than
maxttlallows,traceroutelists the IP addresses for all hops it detects up to themaxttllimit.For any instance of
traceroute, if you want amaxttlvalue other than the default, you must specify that value.(Default: 30)
[
probes <]1-5>For the current instance of
traceroute, changes the number of queries the switch sends for each hop in the route.For any instance of
traceroute, if you want aprobesvalue other than the default, you must specify that value.(Default: 3)
[[source <ip-addr] | [vlan-id>]]
The source IP address or VLAN. The source IP address must be owned by the router. If a VLAN is specified, the IP address associated with the specified VLAN is used.
[
source<ip-addr|vid|loopback <0-7>> ]The source IPv4 address, VLAN ID, or Loopback address.
[
timeout <]1-120>For the current instance of
traceroute, changes the timeout period the switch waits for each probe of a hop in the route. For any instance oftraceroute, if you want atimeoutvalue other than the default, you must specify that value.Default: 5 seconds
NOTE: For information about
traceroute6, see the IPv6 Configuration Guide for your switch.
Executing traceroute with its default values for a destination IP address that is four hops away produces a result similar to this:
Continuing from the previous Example: (A completed traceroute enquiry), executing traceroute with an insufficient maxttl for the actual hop count produces an output similar to this:
Common reasons for traceroute failing to reach a destination include:
Executing traceroute where the route becomes blocked or otherwise fails results in an output marked by timeouts for all probes beyond the last detected hop. For example, with a maximum hop count of 7 (maxttl = 7), where the route becomes blocked or otherwise fails, the output appears similar to this:
