Resolve Network Problems on Windows Operating Systems

To resolve some network problems, you must master a variety of things, namely: understanding some network-related services such as: Routing, DHCP, DNS, Email, Internet Access, Proxy, sub netting, network protocols TCP / IP  and so on. 

In this article, I will be presenting a simple network problem resolution by using the tools that are related to network services on Windows operating systems. On
the Windows operating system, we can take advantage of some network tools such as: ipconfig, ping, nslookup, pathping, tracert and netstat. All the tools we apply via the Command Prompt window that we can open by giving the command cmd in the search field.

ipconfig

ipconfig is a tool to display the network configuration that is used by a computer. Before using other tools, the administrator should examine the results of this tool beforehand to ensure that the configuration is entered manually or obtained from the DHCP server is valid. Options that can be applied are: ipconfig, ipconfig/all, ipconfig/release

ping

This tool is used to test the connection by using the ICMP protocol. In general, network administrators utilize this tool to test network connectivity. Options that can be applied, namely: ping ip_gateway, ping ip_DNSserver, ping ip_client -t, ping ip_server. 

Some messages may appear if the ping fails, namely:

1. Destination Host Unreachable: it means that the transmitted data packets are not able to get to the destination, usually caused by improper routing table in the machine default gateway, or router / hop on it.
2. Request Timed Out: it means that the echo message replay can not be received back within a specified time. This message usually appears as a possible blockade by the firewall of the router or from the target.
3. TTL Expired in Transit: it means that the number of hops (routers) through which to communicate with the server has exceeded the TTL (Time To Live).
4. Ping request could not find host: it means that the server domain resolving on our computers can not translate into an IP address. This is usually caused because the DNS client settings is wrong or our communication with the DNS server is interrupted / disconnected.

nslookup
nslookup is used to diagnose the DNS server service, perform a query to map a domain to IP address or vice versa. nslookup tools can also be used to determine the mx (mail server) or ns (nameserver) responsible for a domain. 
Options that can be applied are : nslookup press enter and set query=mx or set query=ns

Example: nslookup to demakkab.go.id site.

tracert

tracert or traceroute, is a tool to show the path or the routing of data packets traveling between your computer to another computer (server). This tool will display the number of hops (routers) are traversed when heading to the target server.

Options that can be used: tracert ip_server/domain, tracert -d ip_server/domain 

    tracert ip_server/domain

tracert -d ip_server/domain

PathPing

pathping are tools on the Windows operating system that is used to measure network latency and network loss (in percentage) in certain hops between the source address and destination address.

Options that can be applied: pathping –n, pathping ip_server/domain

pathping -n

pathping ip_server/domain

netstat

netstat or network status is a tool used for various purposes, namely: displays the routing table, showing the services that run on Windows and display port communication protocol that is going on.

Options that can be applied: netstat -an, netstat –rn

netstat -an

netstat -rn

Some of the steps that need to be done if the Internet connection is interrupted as follows:

Step 1: Check the lights on and wired Ethernet network

- If there is no sign of a connection, check the cord

- Check also the lights on the hub / switch includes voltage.

Step 2: Make sure the IP configuration, the default gateway and DNS server are correct.

- Check using the tool ipconfig and ipconfig/all.

- Use the tool ipconfig/release, ipconfig/renew to the network using DHCP.

Step 3: ping Default Gateway

- IP default gateway can be seen through the ipconfig command

Step 4: Ping DNS and proxy server if the policy network must use

Proxy.

Step 5: If all is successful, try to ping and tracert to IP_DNS_server and IP_server_proxy

Step 6: If all is successful, try to ping and tracert to sites like:: www.facebook.com