[OpenAFS] OpenAFS 1.0.2: Client vs. Server problem

Karsten Petersen karsten.petersen@informatik.tu-chemnitz.de
Sat, 17 Feb 2001 19:18:32 +0100 (CET)


Hi,

I am using OpenAFS 1.0.2 on my Linux 2.2.16 workstation at home.
(It is masqueraded, using another Linux 2.2 box.)

Access to some parts of my university's AFS-tree works as it should,
but some other parts simply hang the command.  :-(
The remaining system is not compromised, but after Ctrl-C'ing the
hanging command the idle-load raises to 1...

When looking at the network with a sniffer, I could see that first
everything works as (I believe) it should.  The masquerading is working,
there are no lost or incorrectly (e.g. wrong port) send packets.
But then client and server are falling into some "loop", the client
sends "FS Request"s forever - and those packets don't differ as far as
I see  :-/

(I am appending an overview and the details of two of those packets.)

What is happening here?  Is this a problem at the server or at the
client side?  The masquerading should not be the problem, or...?
What kind of tests could I make to get closer to the problem?

Thanks in advance.


The sniffers output:
(dollerup ist the masquerading box, phoenix and ormus are AFS servers)

> From      To       Proto     Info
> dollerup  phoenix  AFS (RX)  VLDB Request: get-entry-by-name-u (527)
>  phoenix dollerup  AFS (RX)  VLDB Reply: get-entry-by-name-u (527)
> dollerup    ormus  AFS (RX)  FS Request: fetch-status (132)
>    ormus dollerup  AFS (RX)  FS Reply: fetch-status (132)
> dollerup    ormus  AFS (RX)  FS Request: fetch-status (132)
>    ormus dollerup  AFS (RX)  FS Reply: fetch-status (132)
> dollerup  phoenix  RX        Type: ack  Seq: 0  Call: 21  Source Port: 61000  Destination Port: 7003
> dollerup    ormus  RX        Type: ack  Seq: 0  Call: 6  Source Port: 61000  Destination Port: 7000
> dollerup    ormus  AFS (RX)  FS Request: fetch-status (132)
>    ormus dollerup  AFS (RX)  FS Reply: fetch-status (132)
> dollerup    ormus  AFS (RX)  FS Request: fetch-status (132)
>    ormus dollerup  AFS (RX)  FS Reply: fetch-status (132)
> dollerup    ormus  AFS (RX)  FS Request: fetch-status (132)
>    ormus dollerup  AFS (RX)  FS Reply: fetch-status (132)
> dollerup    ormus  AFS (RX)  FS Request: fetch-status (132)
>    ormus dollerup  AFS (RX)  FS Reply: fetch-status (132)
> dollerup    ormus  AFS (RX)  FS Request: fetch-status (132)
>    ormus dollerup  AFS (RX)  FS Reply: fetch-status (132)
> ....


Two Frames in detail:   (first the FS Request, then the FS Reply)

> Frame 144 (86 on wire, 86 captured)
>     Arrival Time: Feb 17, 2001 17:36:13.8367
>     Time delta from previous packet: 0.001252 seconds
>     Frame Number: 144
>     Packet Length: 86 bytes
>     Capture Length: 86 bytes
> Ethernet II
>     Destination: 00:90:04:d2:a6:44 (00:90:04:d2:a6:44)
>     Source: 00:20:35:43:ec:60 (IBM_43:ec:60)
>     Type: IP (0x0800)
> Internet Protocol
>     Version: 4
>     Header length: 20 bytes
>     Differentiated Services Field: 0x00 (DSCP 0x00: Default)
>         0000 00.. = Differentiated Services Codepoint: Default (0x00)
>         .... ..00 = Currently Unused: 0
>     Total Length: 72
>     Identification: 0x46b3
>     Flags: 0x00
>         .0.. = Don't fragment: Not set
>         ..0. = More fragments: Not set
>     Fragment offset: 0
>     Time to live: 63
>     Protocol: UDP (0x11)
>     Header checksum: 0xb608 (correct)
>     Source: dollerup.csn.tu-chemnitz.de (134.109.108.5)
>     Destination: ormus.hrz.tu-chemnitz.de (134.109.6.10)
> User Datagram Protocol
>     Source port: 61000 (61000)
>     Destination port: 7000 (7000)
>     Length: 52
>     Checksum: 0x89c8
> RX Protocol (data)
>     Epoch: 2733893784
>     CID: 1816668992
>     Call Number: 8
>     Sequence Number: 1
>     Serial: 12
>     Type: data (1)
>     Flags: 0x05
>         ...0 .... = Free Packet: 0
>         .... 0... = More Packets: 0
>         .... .1.. = Last Packet: 1
>         .... ..0. = Request Ack: 0
>         .... ...1 = Client Initiated: 1
>     User Status: 0
>     Security Index: 2
>     Spare/Checksum: 36616
>     Service ID: 1
> Andrew File System (AFS)
>     Service: File Server Request
>     Operation: fetch-status (132)
>         FileID (Target)
>             FileID (Volume): 536877426
>             FileID (VNode): 1
>             FileID (Uniqifier): 1
>
>    0  0090 04d2 a644 0020 3543 ec60 0800 4500   .....D. 5C.`..E.
>   10  0048 46b3 0000 3f11 b608 866d 6c05 866d   .HF...?....ml..m
>   20  060a ee48 1b58 0034 89c8 a2f3 e898 6c48   ...H.X.4......lH
>   30  2b40 0000 0008 0000 0001 0000 000c 0105   +@..............
>   40  0002 8f08 0001 0000 0084 2000 1972 0000   .......... ..r..
>   50  0001 0000 0001                            ......
>
> Frame 145 (190 on wire, 190 captured)
>     Arrival Time: Feb 17, 2001 17:36:13.8510
>     Time delta from previous packet: 0.014281 seconds
>     Frame Number: 145
>     Packet Length: 190 bytes
>     Capture Length: 190 bytes
> Ethernet II
>     Destination: 00:20:35:43:ec:60 (IBM_43:ec:60)
>     Source: 00:90:04:d2:a6:44 (00:90:04:d2:a6:44)
>     Type: IP (0x0800)
> Internet Protocol
>     Version: 4
>     Header length: 20 bytes
>     Differentiated Services Field: 0x00 (DSCP 0x00: Default)
>         0000 00.. = Differentiated Services Codepoint: Default (0x00)
>         .... ..00 = Currently Unused: 0
>     Total Length: 176
>     Identification: 0x97f9
>     Flags: 0x04
>         .1.. = Don't fragment: Set
>         ..0. = More fragments: Not set
>     Fragment offset: 0
>     Time to live: 252
>     Protocol: UDP (0x11)
>     Header checksum: 0x6759 (correct)
>     Source: ormus.hrz.tu-chemnitz.de (134.109.6.10)
>     Destination: dollerup.csn.tu-chemnitz.de (134.109.108.5)
> User Datagram Protocol
>     Source port: 7000 (7000)
>     Destination port: 61000 (61000)
>     Length: 156
>     Checksum: 0xfb07
> RX Protocol (data)
>     Epoch: 2733893784
>     CID: 1816668992
>     Call Number: 8
>     Sequence Number: 1
>     Serial: 9
>     Type: data (1)
>     Flags: 0x04
>         ...0 .... = Free Packet: 0
>         .... 0... = More Packets: 0
>         .... .1.. = Last Packet: 1
>         .... ..0. = Request Ack: 0
>         .... ...0 = Client Initiated: 0
>     User Status: 0
>     Security Index: 2
>     Spare/Checksum: 36616
>     Service ID: 1
> Andrew File System (AFS)
>     Service: File Server Reply
>     Operation: fetch-status (132)
>
>    0  0020 3543 ec60 0090 04d2 a644 0800 4500   . 5C.`.....D..E.
>   10  00b0 97f9 4000 fc11 6759 866d 060a 866d   ....@...gY.m...m
>   20  6c05 1b58 ee48 009c fb07 a2f3 e898 6c48   l..X.H........lH
>   30  2b40 0000 0008 0000 0001 0000 0009 0104   +@..............
>   40  0002 8f08 0001 0000 0001 0000 0002 0000   ................
>   50  000a 0000 0800 0000 1e79 0000 00c9 0000   .........y......
>   60  0000 0000 0009 0000 0009 0000 01ed 0000   ................
>   70  0001 0000 0001 0000 0000 383c e07f 383c   ..........8<..8<
>   80  e07f 0000 0000 0000 0000 0000 0000 0000   ................
>   90  0000 0000 0000 0000 0001 0000 0001 0000   ................
>   a0  0000 0000 0002 301f 3d01 0000 0000 0000   ......0.=.......
>   b0  0000 0000 0000 0000 0000 0000 0000        ..............


Greets, Karsten
-- 
10./11.3.:  3. Chemnitzer Linux-Tag:  http://www.tu-chemnitz.de/linux/tag/
,-,  Student of Computer Science at Chemnitz University of Technology  ,-,
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