In the Vol II  section 1 multiprotocol Challenge  A  task 2.2  we have to leak 
additional routes  into R2  so everything stays connected if one of the link 
goes down.  I understand that.   I know that I need /32 for routes later on.

What I do not understand is why R1 and R5, the L1/L2 routers  do not leak a 
default route into R2.    I thought the L1/L2 routers were supposed to set the 
ATT   bit so R2 has a way out of the network

R2#
IS-IS Level-1 Link State Database:
LSPID                 LSP Seq Num  LSP Checksum  LSP Holdtime      ATT/P/OL
R1.00-00              0x00000031   0x6E4B        1058              0/0/0
R2.00-00            * 0x00000032   0x4661        977               0/0/0
R5.00-00              0x00000035   0xAECD        980               0/0/0
R5.03-00              0x00000008   0x2B7D        960               0/0/0


R1#sh isi database

IS-IS Level-1 Link State Database:
LSPID                 LSP Seq Num  LSP Checksum  LSP Holdtime      ATT/P/OL
R1.00-00            * 0x00000031   0x6E4B        891               0/0/0
R2.00-00              0x00000032   0x4661        806               0/0/0
R5.00-00              0x00000035   0xAECD        809               0/0/0
R5.03-00              0x00000008   0x2B7D        790               0/0/0
IS-IS Level-2 Link State Database:
LSPID                 LSP Seq Num  LSP Checksum  LSP Holdtime      ATT/P/OL
R1.00-00            * 0x0000000B   0x0EBF        886               0/0/0
R5.00-00              0x0000000B   0x1228        518               0/0/0
R1#

R5#sh is database

IS-IS Level-1 Link State Database:
LSPID                 LSP Seq Num  LSP Checksum  LSP Holdtime      ATT/P/OL
R1.00-00              0x00000031   0x6E4B        844               0/0/0
R2.00-00              0x00000032   0x4661        763               0/0/0
R5.00-00            * 0x00000035   0xAECD        769               0/0/0
R5.03-00            * 0x00000008   0x2B7D        750               0/0/0
IS-IS Level-2 Link State Database:
LSPID                 LSP Seq Num  LSP Checksum  LSP Holdtime      ATT/P/OL
R1.00-00              0x0000000B   0x0EBF        840               0/0/0
R5.00-00            * 0x0000000B   0x1228        476               0/0/0



I do not see any ATT bit being set and L2 is definitely an L1 only router and 
R! and R5 are definitely L1/L2 routers.  In Doyles' Volume 1 Routing book page 
580 he discusses this and suggests turning on CLNS routing on both the 
interface and the routers (default)  I did that and am still not getting the 
ATT bit set.

What am I doing wrong?  AM I wrong to look for the ATT bit / default route in 
this scenario?

All three routers are 7200 running version 12.2(18)S2

thanks

Thomas Loran
CCIE  #7113

_______________________________________________
For more information regarding industry leading CCIE Lab training, please visit 
www.ipexpert.com

Reply via email to