OpenVPN netsh command failed: returned error code 1

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Common OpenVPN Error Messages – And How to Fix Them!
If the handshake fails we will attempt to reset our connection with our peer and try again. Adaptive compression tries to optimize the case where you have compression enabled, but you are sending predominantly uncompressible or pre-compressed packets over the tunnel, such as an FTP or rsync transfer of a large, compressed file. The purpose of such a call would normally be to block until the device or socket is ready to accept the write. Replay protection is important to defeat attacks such as a SYN flood attack, where the attacker listens in the wire, intercepts a TCP SYN packet identifying it by the context in which it occurs in relation to other packets , then floods the receiving peer with copies of this packet. This directive is designed to enable a plugin-style interface for extending OpenVPN's authentication capabilities. The optional progname parameter will cause OpenVPN to report its program name to the system logger as progname.

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Windows: issue: netsh command failed: returned error code 1

See "systemctl status openvpn server. Add comments here to get more clarity or context around a question. Reboor system after that. Enter again sudo systemctl start openvpn server and the mistake have to disapear. I followed the same tutorial and am having the same problem. This is all very new to me so I apologise in advance if I have made a basic error but I really don't know what's gone wrong.

Starting OpenVPN connection to server Failed to start OpenVPN connection to server. Unit entered failed state. Failed with result 'exit-code'. Having similar problem hopefully this will get an answer soon. When I run the "systemctl start openvpn server. I have output from systemctl status command, the journalctl -xe command and the OpenVPN. If you need the output from the other two I can post it. No such file or directory Options error: Please correct these errors.

Use --help for more information. Do a search in the directory and you will see that the file is named "ta-key" and not ta. See the OpenVPN 1. If file already exists it will be truncated. This option takes effect immediately when it is parsed in the command line and will supercede syslog output if --daemon or --inetd is also specified.

Note that on Windows, when OpenVPN is started as a service, logging occurs by default without the need to specify this option. If file does not exist, it will be created. This option behaves exactly like --log except that it appends to rather than truncating the log file.

In particular, this applies to log messages sent to stdout. The purpose of such a call would normally be to block until the device or socket is ready to accept the write. This option can only be used on non-Windows systems, when --proto udp is specified, and when --shaper is NOT specified.

This option can be used when OpenVPN has been configured to listen on all interfaces, and will attempt to bind client sessions to the interface on which packets are being received, so that outgoing packets will be sent out of the same interface.

Note that this option is only relevant for UDP servers and currently is only implemented on Linux. Designed to be used to send messages to a controlling application which is receiving the OpenVPN log output.

By default, no remapping occurs. Each level shows all info from the previous levels. Level 3 is recommended if you want a good summary of what's happening without being swamped by output. Currently n can be 1, 2, or 3 and defaults to 1.

This is useful to limit repetitive logging of similar message types. In a server mode setup, it is possible to selectively turn compression on or off for individual clients. First, make sure the client-side config file enables selective compression by having at least one --comp-lzo directive, such as --comp-lzo no.

Next in a --client-config-dir file, specify the compression setting for the client, for example: Normally, adaptive compression is enabled with --comp-lzo. Adaptive compression tries to optimize the case where you have compression enabled, but you are sending predominantly uncompressible or pre-compressed packets over the tunnel, such as an FTP or rsync transfer of a large, compressed file.

With adaptive compression, OpenVPN will periodically sample the compression process to measure its efficiency. If the data being sent over the tunnel is already compressed, the compression efficiency will be very low, triggering openvpn to disable compression for a period of time until the next re-sample test.

The password provided will set the password which TCP clients will need to provide in order to access management functions. The management interface can also listen on a unix domain socket, for those platforms that support it.

To use a unix domain socket, specify the unix socket pathname in place of IP and set port to 'unix'. While the default behavior is to create a unix domain socket that may be connected to by any process, the --management-client-user and --management-client-group directives can be used to restrict access. The management interface provides a special mode where the TCP management link can operate over the tunnel itself. While the management port is designed for programmatic control of OpenVPN by other applications, it is possible to telnet to the port, using a telnet client in "raw" mode.

Once connected, type "help" for a list of commands. For detailed documentation on the management interface, see the management-notes. It is strongly recommended that IP be set to Only query the management channel for inputs which ordinarily would have been queried from the console.

It is always cached. This is useful when you wish to disconnect an OpenVPN session on user logoff. Multiple plugin modules may be loaded into one OpenVPN process. The documentation is in doc and the actual plugin modules are in lib. Multiple plugin modules can be cascaded, and modules can be used in tandem with scripts.

The modules will be called by OpenVPN in the order that they are declared in the config file. If both a plugin and script are configured for the same callback, the script will be called last.

In server mode, OpenVPN will listen on a single port for incoming client connections. All client connections will be routed through a single tun or tap interface. This mode is designed for scalability and should be able to support hundreds or even thousands of clients on sufficiently fast hardware.

The server itself will take the ". For example, --server The optional nogw flag advanced indicates that gateway information should not be pushed to the client. For example, server-bridge Note that option must be enclosed in double quotes "". The client must specify --pull in its config file. The set of options which can be pushed is limited by both feasibility and security.

Some options such as those which would execute scripts are banned, since they would effectively allow a compromised server to execute arbitrary code on the client. Other options such as TLS or MTU parameters cannot be pushed because the client needs to know them before the connection to the server can be initiated.

This is a partial list of options which can currently be pushed: Specify this option in a client-specific context such as with a --client-config-dir configuration file.

This option will ignore --push options at the global config file level. Don't use this option to disable a client due to key or password compromise. Use a CRL certificate revocation list instead see the --crl-verify option.

This option must be associated with a specific client instance, which means that it must be specified either in a client instance config file using --client-config-dir or dynamically generated using a --client-connect script. For tap-style tunnels, individual addresses will be allocated, and the optional netmask parameter will also be pushed to clients. The goal of this option is to provide a long-term association between clients denoted by their common name and the virtual IP address assigned to them from the ifconfig-pool.

Maintaining a long-term association is good for clients because it allows them to effectively use the --persist-tun option. This is useful if you would like to treat file as a configuration file. Note that the entries in this file are treated by OpenVPN as suggestions only, based on past associations between a common name and IP address. They do not guarantee that the given common name will always receive the given IP address. This option is incompatible with Windows clients.

This option is deprecated, and should be replaced with --topology p2p which is functionally equivalent. The parameters local and remote-netmask are set according to the --ifconfig directive which you want to execute on the client machine to configure the remote end of the tunnel.

Note that the parameters local and remote-netmask are from the perspective of the client, not the server. They may be DNS names rather than IP addresses, in which case they will be resolved on the server at the time of client connection. The netmask parameter, if omitted, defaults to This directive can be used to route a fixed subnet from the server to a particular client, regardless of where the client is connecting from.

Remember that you must also add the route to the system routing table as well such as by using the --route directive. The reason why two routes are needed is that the --route directive routes the packet from the kernel to OpenVPN. Once in OpenVPN, the --iroute directive routes to the specific client. This option must be specified either in a client instance config file using --client-config-dir or dynamically generated using a --client-connect script. The --iroute directive also has an important interaction with --push "route If you would like other clients to be able to reach A's subnet, you can use --push "route OpenVPN accomplishes this by not not pushing a route to a client if it matches one of the client's iroutes.

When this option is used, each client will "see" the other clients which are currently connected. Otherwise, each client will only see the server. Don't use this option if you want to firewall tunnel traffic using custom, per-client rules. In the absence of this option, OpenVPN will disconnect a client instance upon connection of a new client having the same common name.

The script is passed the common name and IP address of the just-authenticated client as environmental variables see environmental variable section below. See the --client-config-dir option below for options which can be legally used in a dynamically generated config file.

Note that the return value of script is significant. If script returns a non-zero error status, it will cause the client to be disconnected. Will not be called unless the --client-connect script and plugins if defined were previously called on this instance with successful 0 status returns.

The exception to this rule is if the --client-disconnect script or plugins are cascaded, and at least one client-connect function succeeded, then ALL of the client-disconnect functions for scripts and plugins will be called on client instance object deletion, even in cases where some of the related client-connect functions returned an error status.

After a connecting client has been authenticated, OpenVPN will look in this directory for a file having the same name as the client's X common name. If a matching file exists, it will be opened and parsed for client-specific configuration options.

This file can specify a fixed IP address for a given client using --ifconfig-push, as well as fixed subnets owned by the client using --iroute. One of the useful properties of this option is that it allows client configuration files to be conveniently created, edited, or removed while the server is live, without needing to restart the server. The following options are legal in a client-specific context: This directory will be used by --client-connect scripts to dynamically generate client-specific configuration files.

By default, both tables are sized at buckets. When the number of output packets queued before sending to the TCP socket reaches this limit for a given client connection, OpenVPN will start to drop outgoing packets directed at this client. The macro expands as follows: This is designed to help contain DoS attacks where an authenticated client floods the server with packets appearing to come from many unique MAC addresses, forcing the server to deplete virtual memory as its internal routing table expands.

This directive can be used in a --client-config-dir file or auto-generated by a --client-connect script to override the global value for a particular client. Note that this directive affects OpenVPN's internal routing table, not the kernel routing table.

This is designed to contain DoS attacks which flood the server with connection requests using certificates which will ultimately fail to authenticate. This is an imperfect solution however, because in a real DoS scenario, legitimate connections might also be refused. For the best protection against DoS attacks in server mode, use --proto udp and --tls-auth.

This can be an IPv4 address such as " Only present for "add" or "update" operations, not "delete". On "add" or "update" methods, if the script returns a failure code non-zero , OpenVPN will reject the address and will not modify its internal routing table.

Since OpenVPN provides the association between virtual IP or MAC address and the client's authenticated common name, it allows a user-defined script to configure firewall access policies with regard to the client's high-level common name, rather than the low level client virtual addresses. Be aware that this method is insecure on some platforms which make the environment of a process publicly visible to other unprivileged processes. If method is set to "via-file", OpenVPN will write the username and password to the first two lines of a temporary file.

The filename will be passed as an argument to script, and the file will be automatically deleted by OpenVPN after the script returns. The location of the temporary file is controlled by the --tmp-dir option, and will default to the current directory if unspecified.

The script should examine the username and password, returning a success exit code 0 if the client's authentication request is to be accepted, or a failure code 1 to reject the client.

This directive is designed to enable a plugin-style interface for extending OpenVPN's authentication capabilities. To protect against a client passing a maliciously formed username or password string, the username string must consist only of these characters: The password string can consist of any printable characters except for CR or LF.

Care must be taken by any user-defined scripts to avoid creating a security vulnerability in the way that these strings are handled. Never use these strings in such a way that they might be escaped or evaluated by a shell interpreter. Options that will be compared for compatibility include dev-type, link-mtu, tun-mtu, proto, tun-ipv6, ifconfig, comp-lzo, fragment, keydir, cipher, auth, keysize, secret, no-replay, no-iv, tls-auth, key-method, tls-server, and tls-client.

This option requires that --disable-occ NOT be used. Normally, when --auth-user-pass-verify or --management-client-auth is specified or an authentication plugin module , the OpenVPN server daemon will require connecting clients to specify a username and password. Be aware that using this directive is less secure than requiring certificates from all clients.

If you use this directive, the entire responsibility of authentication will rest on your --auth-user-pass-verify script, so keep in mind that bugs in your script could potentially compromise the security of your VPN. If you don't use this directive, but you also specify an --auth-user-pass-verify script, then OpenVPN will perform double authentication. The client certificate verification AND the --auth-user-pass-verify script will need to succeed in order for a client to be authenticated and accepted onto the VPN.

While name remapping is performed for security reasons to reduce the possibility of introducing string expansion security vulnerabilities in user-defined authentication scripts, this option is provided for those cases where it is desirable to disable the remapping feature.

Don't use this option unless you know what you are doing! Not implemented on Windows. Client Mode Use client mode when connecting to an OpenVPN server which has --server, --server-bridge, or --mode server in it's configuration. This directive is equivalent to: It indicates to OpenVPN that it should accept options pushed by the server, provided they are part of the legal set of pushable options note that the --pull option is implied by --client. In particular, --pull allows the server to push routes to the client, so you should not use --pull or --client in situations where you don't trust the server to have control over the client's routing table.

Use this option for unattended clients. Note that while this option cannot be pushed, it can be controlled from the management interface. Data Channel Encryption Options: Use pre-shared secret file which was generated with --genkey. This has a number of desirable security properties including eliminating certain kinds of DoS and message replay attacks. The direction parameter should always be complementary on either side of the connection, i.

The direction parameter requires that file contains a bit key. Static key encryption mode has certain advantages, the primary being ease of configuration.

There are no certificates or certificate authorities or complicated negotiation handshakes and protocols. The only requirement is that you have a pre-existing secure channel with your peer such as ssh to initially copy the key. This requirement, along with the fact that your key never changes unless you manually generate a new one, makes it somewhat less secure than TLS mode see below.

If an attacker manages to steal your key, everything that was ever encrypted with it is compromised. Contrast that to the perfect forward secrecy features of TLS mode using Diffie Hellman key exchange , where even if an attacker was able to steal your private key, he would gain no information to help him decrypt past sessions. Another advantageous aspect of Static Key encryption mode is that it is a handshake-free protocol without any distinguishing signature or feature such as a header or protocol handshake sequence that would mark the ciphertext packets as being generated by OpenVPN.

Anyone eavesdropping on the wire would see nothing but random-looking data. The default is SHA1. HMAC is a commonly used message authentication algorithm MAC that uses a data string, a secure hash algorithm, and a key, to produce a digital signature. In static-key encryption mode, the HMAC key is included in the key file generated by --genkey.

HMAC usually adds 16 or 20 bytes per packet. For more information on HMAC see http: Blowfish has the advantages of being fast, very secure, and allowing key sizes of up to bits. Blowfish is designed to be used in situations where keys are changed infrequently.

For more information on blowfish, see http: If unspecified, defaults to cipher-specific default. The --show-ciphers option see below shows all available OpenSSL ciphers, their default key sizes, and whether the key size can be changed. Use care in changing a cipher's default key size. Many ciphers have not been extensively cryptanalyzed with non-standard key lengths, and a larger key may offer no real guarantee of greater security, or may even reduce security.

If engine-name is specified, use a specific crypto engine. Use the --show-engines standalone option to list the crypto engines which are supported by OpenSSL. Don't use this option unless you are prepared to make a tradeoff of greater efficiency in exchange for less security. OpenVPN provides datagram replay protection by default. Replay protection is accomplished by tagging each outgoing datagram with an identifier that is guaranteed to be unique for the key being used.

The peer that receives the datagram will check for the uniqueness of the identifier. If the identifier was already received in a previous datagram, OpenVPN will drop the packet.

Replay protection is important to defeat attacks such as a SYN flood attack, where the attacker listens in the wire, intercepts a TCP SYN packet identifying it by the context in which it occurs in relation to other packets , then floods the receiving peer with copies of this packet.

OpenVPN's replay protection is implemented in slightly different ways, depending on the key management mode you have selected. By default n is 64 the IPSec default and t is 15 seconds. This option is only relevant in UDP mode, i. If you are using a network link with a large pipeline meaning that the product of bandwidth and latency is high , you may want to use a larger value for n. Satellite links in particular often require this. If you run OpenVPN at --verb 4, you will see the message "Replay-window backtrack occurred [x]" every time the maximum sequence number backtrack seen thus far increases.

This can be used to calibrate n. There is some controversy on the appropriate method of handling packet reordering at the security layer. Namely, to what extent should the security layer protect the encapsulated protocol from attacks which masquerade as the kinds of normal packet loss and reordering that occur over IP networks? Since TCP guarantees reliability, any packet loss or reordering event can be assumed to be an attack. In this sense, it could be argued that TCP tunnel transport is preferred when tunneling non-IP or UDP application protocols which might be vulnerable to a message deletion or reordering attack which falls within the normal operational parameters of IP networks.

So I would make the statement that one should never tunnel a non-IP protocol or UDP application protocol over UDP, if the protocol might be vulnerable to a message deletion or reordering attack that falls within the normal operating parameters of what is to be expected from the physical IP layer. This option preserves the security of the replay protection code without the verbosity associated with warnings about duplicate packets. This option will strengthen protection against replay attacks, especially when you are using OpenVPN in a dynamic context such as with --inetd when OpenVPN sessions are frequently started and stopped.

This option will keep a disk copy of the current replay protection state i. This option only makes sense when replay protection is enabled the default and you are using either --secret shared-secret key mode or TLS mode with --tls-auth. IV is implemented differently depending on the cipher mode used. This option does not require a peer to function, and therefore can be specified without --dev or --remote.

The typical usage of --test-crypto would be something like this: Since it is a self-test mode, problems with encryption and authentication can be debugged independently of network and tunnel issues. TLS mode uses a robust reliability layer over the UDP connection for all control channel communication, while the data channel, over which encrypted tunnel data passes, is forwarded without any mediation.

The result is the best of both worlds: When two OpenVPN peers connect, each presents its local certificate to the other. Each peer will then check that its partner peer presented a certificate which was signed by the master root certificate as specified in --ca. If that check on both peers succeeds, then the TLS negotiation will succeed, both OpenVPN peers will exchange temporary session keys, and the tunnel will begin passing data.

The easy-rsa package is also rendered in web form here: Note that OpenVPN is designed as a peer-to-peer application. The designation of client or server is only for the purpose of negotiating the TLS control channel. This file can have multiple certificates in. You can construct your own certificate authority certificate and private key by using a command such as: Yes, this has to be due to dhcp disabled in the adapter and openvpn started using interactive service.

As cron2 said, it did come up in the past: As suggested there we better implement dhcp mode setting through interactive service. Though not relevant here, also mutate --ip-win32 netsh to ipapi so that a run as admin with that option will not disable dhcp. As a quick fix, set the adapter to use dhcp and reconnect: Powered by Trac 1. Visit the Trac open source project at http: Opened 17 months ago Last modified 17 months ago.

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