RS232 heartbeat - remote solution wanted - Aix

This is a discussion on RS232 heartbeat - remote solution wanted - Aix ; In a nutshell - looking for examples of a super rock solid RS232 remote solution for the heartbeat plumbing across a WAN..... Can't use disk SAN or other alternatives at this time. We are already using IBM's HACMP for AIX. ...

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Thread: RS232 heartbeat - remote solution wanted

  1. RS232 heartbeat - remote solution wanted

    In a nutshell - looking for examples of a super rock solid RS232 remote solution
    for the heartbeat plumbing across a WAN.....
    Can't use disk SAN or other alternatives at this time.

    We are already using IBM's HACMP for AIX. It's a single site and we
    currently have a simple serial cable running under the floor for the
    "NON IP HEARTBEAT." There is additional heartbeating going on over IP.
    This serial heartbeat is used to prevent a split brain when the network
    goes away. This machine is now being moved to a remote site for backup.

    The software used for heartbeating basically comes with AIX, it's called
    RSCT, or Reliable Scalable Cluster Technology.

    I don't think there is much of a protocol, I think the node just listens
    for the packets to come in, and if all heartbeat packets stop coming in,
    it assumes the other node is down. We have been able to find some
    documentation about how it works - for example, we know the nodes
    'handshake' and 9600, then switch to 38400 by default. We also have
    instructions for changing this behavior - hardcoding to 9600. But once
    that initial handshake is done, and the cluster is stable, I'm pretty
    sure it's just each node listening for the packets to stop coming in.

    Right ??? there are packets vs just RS232 signals being toggled ?

    A T1 circuit that we are using for the serial over IP is completely
    separate - it's will only be used for this purpose.

    Yeah, the devices we bought (terminal servers) are the big brother to
    the Lantronix serial devices. Lots of ports, and more options. However, I
    wonder if we should have chosen terminal servers, as we are not trying
    to 'serve terminals', lol. As a matter of fact, we can get a login
    prompt across the WAN, so connectivity is there, and the devices are
    'basically working.' They just aren't working reliably enough for
    these heartbeats, and they occasionally go down. Sometimes errors pop up
    in the logs, or the 'heartbeat network' pops up and down.

    Looking for any of your real world implemented solutions
    to create a rock solid RS232 remote heartbeat network...



  2. Re: RS232 heartbeat - remote solution wanted

    On 2007-05-17, P.Schuman wrote:
    > Yeah, the devices we bought (terminal servers) are the big brother to
    > the Lantronix serial devices. Lots of ports, and more options. However, I
    > wonder if we should have chosen terminal servers, as we are not trying
    > to 'serve terminals', lol. As a matter of fact, we can get a login
    > prompt across the WAN, so connectivity is there, and the devices are
    > 'basically working.' They just aren't working reliably enough for
    > these heartbeats, and they occasionally go down. Sometimes errors pop up
    > in the logs, or the 'heartbeat network' pops up and down.
    >
    > Looking for any of your real world implemented solutions
    > to create a rock solid RS232 remote heartbeat network...


    At my former company we used serial-to-ISDN converters and
    IIRC leased line ISDN connections. But even those had some-
    times hiccups, which resulted in errlog entries complaining
    about a short loss of heartbeat.

    Regards,

    Frank

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