[syslinux] extlinux 6.03 serial console not responding to input

[Ferenc Wagner]

"Andrew J. Schorr via Syslinux" <syslinux at zytor.com> writes:

> I just upgraded some systems from Fedora 19 (extlinux 4.05)
> to Fedora 21 (extlinux 6.03).  I am using IPMI 2.0 serial-over-lan
> console redirection.  Under the old version, this worked without
> any problem:
>
>    serial 0 57600 0x003
>    ui menu.c32
>    menu title ExtLinux Boot Menu
>    timeout 100
>
>    label Linux1
>    ...
>
> Using the new version of extlinux in Fedora 21, I can no longer communicate
> with the extlinux boot menu.  It does not see anything that I type.
> I tried grub2, and that works fine.
>
> I tried removing the flowcontrol flag bits, and I also tried 0x00b,
> but nothing works.

I hit the same problem on Fujitsu Primergy CX250 S2 servers.  I ended up
relying on the BIOS console redirection instead of using the native
serial support in Syslinux.  It isn't a generic problem, though, as at
least virtual machines can receive serial input under 6.03.  Testing
intermediate versions would help finding the problem, but recently I
can't request much downtime on these servers.
-- 
Regards,
Feri.