Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On Thursday 23 September 2004 15:19, you wrote: > Hi Philipp, > > Thank you for your comments. I will assume that DRBD-0.8 is at least 6 > months out and I am in need of a work around. This means that I will > probably try and implement your suggested fix in 0.6.12 and then send it to > the development list for comments. > > Do you have any pointers for me (prototype) that may save me time as I look to tackle this issue. My company will not allow me to use drbd in production unless I can demonstrate a stable subsystem. I appreciate any help. Following I have attached the section from 0.8 roadmap that deals with this issue: > > 5 It is possible that a secondary node crashes a primary by > > returning invalid block_ids in ACK packets. [This might be > > either caused by faulty hardware, or by a hostile modification > > of DRBD on the secondary node] > > > > Proposed solution: > > > > Extend the block_id field. (currently 64 bit) by at least > > 32 bits (64?) . (=block_id_chk field). The primary node > > stores an encrypted (random key, changes every 15 minutes...) > > checksum (=signature) in the second field. > > > > The secondary node can not fake (either intentionally or > > unintentionally) these signature. > > > > The primary node will only dereference the block_id pointers > > if the signature is right. > > Best Regards, > Moiz > * Why do you want to use drbd-0.6.x ? Why do you not use drbd-0.7.x ? * You have to fix the RAM of the secondary machine. (In case you really have the issue you reference to) Maybe you should post that OOPS ... The item 5 of drbd-0.8 roadmap will have the effect that the primary node will write something like "Got invalid block-id" to its Syslog and disconnect. --> You have to fix the RAM of the secondary... * Ever considered that it might be chaper to ask DRBD's authors to do that featur for drbd-0.7 (by getting in contact with office at linbit.com) than understanding the internals of DRBD by yourself ? Just in case you need to protect yourself agains failing RAMs in your machines :) -Philipp -- : Dipl-Ing Philipp Reisner Tel +43-1-8178292-50 : : LINBIT Information Technologies GmbH Fax +43-1-8178292-82 : : Schönbrunnerstr 244, 1120 Vienna, Austria http://www.linbit.com :