SYSLINUX | |
by H. Peter Anvin |
Failed to free base memory, sorry...... when that happens. It should not cause problems other than the loss of some memory; usually about 64K worth. PXELINUX 2.03 or later will display an error code in conjunction with the message; reporting that error code might assist in identifying the location of the problem.
Most, possibly all, PXE implementations are completely broken if they
receive fragmented IP packets; also, a lot of them will request a
blksize of 1468 or thereabouts, corresponding to an MTU of 1500.
Therefore, your boot server should never use an MTU that is
larger than the MTU the packets may encounter during the transfer
(typically 1500), and you should disable the blksize
option (-r blksize
in tftp-hpa) if you have to use an MTU
smaller than 1500. Fortunately it's rare these days that you'll have
that kind of network between your TFTP server and your clients.
http://support.intel.com/support/network/adapter/index.htmIf your network adapter is on the motherboard, you will probably need to request a BIOS upgrade from your system or motherboard vendor.
http://support.3com.com/infodeli/tools/nic/mba.htm
I would like to obtain information of various 3Com MBA versions and whether or not they work. Please send such reports to hpa+cards@zytor.com.
If you can, upgrade your firmware.
Unfortunately, firmware upgrade to a recent source base are frequently unavailable for these cards, especially motherboard cards where the PXE stack is integrated with the system BIOS. If so, these stacks can usually be made to work with the following workarounds:
net.ipv4.ip_no_pmtu_disc
to 1:
echo 1 > /proc/sys/net/ipv4/ip_no_pmtu_disc
Note that that may cause bad performance for other services
which may be running on the boot server, especially if they have to
talk over WAN links. DHCP or TFTP services should generally not be affected.
blksize
TFTP option on your TFTP server.
Some version of these stacks are known to request the
blksize
option and fail to complete the initial bootstrap
transfer if the option is granted by the server (i.e. they got what
they asked for.) For tftp-hpa, specify -r blksize
to
disable blksize
, for atftp specify
--no-blksize
. For other TFTP servers, see your TFTP
server documentation. Note that disabling blksize
may have a
significant impact on the performance of all TFTP clients. Other services
are not affected.
mkisofs
to put the boot
catalogue in the same location as the Windows 2000 one.
One SYSLINUX user recently had an exchange with a representative of GigaByte, which claims USB boot support "is not PC standard". Until GigaByte changes their perception about this, it might be wise to avoid GigaByte motherboards if one wishes to rely on USB boot.