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T1 Bandwidth?

I have a T1 CSU/DSU on a 2621 router and looking at the line

CISCO2#sho int s0/0 Serial0/0 is up, line protocol is up Hardware is PQUICC with Fractional T1 CSU/DSU Internet address is xxx.xxx.xxx.xxx/30 MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec, reliability 255/255, txload 1/255, rxload 1/255 Encapsulation HDLC, loopback not set Keepalive set (10 sec) Last input 00:00:00, output 00:00:00, output hang never Last clearing of "show interface" counters 2d03h Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0 Queueing strategy: weighted fair Output queue: 0/1000/64/0 (size/max total/threshold/drops) Conversations 0/6/256 (active/max active/max total) Reserved Conversations 0/0 (allocated/max allocated) Available Bandwidth 1158 kilobits/sec 5 minute input rate 1000 bits/sec, 2 packets/sec 5 minute output rate 2000 bits/sec, 2 packets/sec

Why is the Available Bandwidth on the Output queue less than the T1 Bandwidth? Can it be increased?

Reply to
Tom Linden
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What is the config for this interface? What are the sh controller commands displaying?

Reply to
Zub

Here is the config interface Serial0/0 ip address 206.XXX.XXX.XXX 255.255.255.252 ip access-group 101 in ip access-group 102 out ip nat outside no ip mroute-cache

CISCO2#sho controllers F0/0 Interface FastEthernet0/0 Hardware is AMD Am79c971 ADDR: 82BF5BD8, FASTSEND: 80027A1C, MCI_INDEX: 0 DIST ROUTE ENABLED: 0 Route Cache Flag: 11 LADRF=3D0x0000 0x0000 0x0000 0x0000 CSR0 =3D0x00000072, CSR3 =3D0x00001044, CSR4 =3D0x0000491D, CSR15 =3D=

0x00000180 CSR80 =3D0x00009900, CSR114=3D0x00000000, CRDA =3D0x03D177E0, CXDA =3D= 0x03D17B10 BCR9 =3D0x00000001 (full-duplex) CSR5 =3D0x00000001, CSR7 =3D0x00000828, CSR100=3D0x0000F000, CSR125=3D= 0x00005C3C BCR2 =3D0x00001000, BCR9 =3D0x00000001, BCR18 =3D0x000019E0, BCR22 =3D= 0x0000FF06 BCR25 =3D0x000000FF, BCR26 =3D0x00000080, BCR27 =3D0x00000010, BCR32 =3D= 0x00004D80 HW filtering information: Promiscuous Mode Disabled, PHY Addr Enabled, Broadcast Addr Enabled PHY Addr=3D00B0.64AD.7900, Multicast Filter=3D0x0000 0x0000 0x0000 0x= 0000 amdp2_instance=3D0x82BF7380, registers=3D0x40000000, ib=3D0x3D17540 rx ring entries=3D64, tx ring entries=3D128 rxring=3D0x3D175A0, rxr shadow=3D0x82BF75F0, rx_head=3D36, rx_tail=3D0=

txring=3D0x3D179E0, txr shadow=3D0x82BF771C, tx_head=3D19, tx_tail=3D1=

9, =

tx_count=3D0 Software MAC address filter(hash:length/addr/mask/hits): spurious_idon=3D0, throttled=3D0, enabled=3D0, disabled=3D0 rx_framing_err=3D0, rx_overflow_err=3D0, rx_buffer_err=3D0 rx_bpe_err=3D0, rx_soft_overflow_err=3D0, rx_no_enp=3D0, rx_discard=3D=

0 tx_one_col_err=3D0, tx_more_col_err=3D0, tx_no_enp=3D0, tx_deferred_er= r=3D0 tx_underrun_err=3D0, tx_late_collision_err=3D0, tx_loss_carrier_err=3D= 0 tx_exc_collision_err=3D0, tx_buff_err=3D0, fatal_tx_err=3D0 hsrp_conf=3D0, need_af_check=3D0 tx_limited=3D0(64) PHY registers: Register 0x00: 1100 782D 7810 0003 0141 01E1 0001 0000 Register 0x08: 0000 0000 0000 0000 0000 0000 0000 0000 Register 0x10: 0000 0000 4000 0000 38C8 0010 0000 0002 Register 0x18: 0001 0000 0000 0000 0000

CISCO2#sho controllers F0/1 Interface FastEthernet0/1 Hardware is AMD Am79c971 ADDR: 82BFB858, FASTSEND: 80027A1C, MCI_INDEX: 0 DIST ROUTE ENABLED: 0 Route Cache Flag: 11 LADRF=3D0x0000 0x0100 0x0000 0x0000 CSR0 =3D0x00000072, CSR3 =3D0x00001044, CSR4 =3D0x0000491D, CSR15 =3D=

0x00000180 CSR80 =3D0x00009900, CSR114=3D0x00000000, CRDA =3D0x03D665C0, CXDA =3D= 0x03D66BF0 BCR9 =3D0x00000001 CSR5 =3D0x00000001, CSR7 =3D0x00000028, CSR100=3D0x0000F000, CSR125=3D= 0x00005C3C BCR2 =3D0x00001000, BCR9 =3D0x00000001, BCR18 =3D0x000019E0, BCR22 =3D= 0x0000FF06 BCR25 =3D0x000000FF, BCR26 =3D0x00000080, BCR27 =3D0x00000010, BCR32 =3D= 0x00004D80 HW filtering information: Promiscuous Mode Disabled, PHY Addr Enabled, Broadcast Addr Enabled PHY Addr=3D00B0.64AD.7901, Multicast Filter=3D0x0000 0x0100 0x0000 0x= 0000 amdp2_instance=3D0x82BFD000, registers=3D0x40100000, ib=3D0x3D66260 rx ring entries=3D64, tx ring entries=3D128 rxring=3D0x3D662C0, rxr shadow=3D0x82BFD270, rx_head=3D48, rx_tail=3D0=

txring=3D0x3D66700, txr shadow=3D0x82BFD39C, tx_head=3D79, tx_tail=3D7=

9, =

tx_count=3D0 Software MAC address filter(hash:length/addr/mask/hits): 0xC0: 0 0100.0ccc.cccc 0000.0000.0000 0 spurious_idon=3D0, throttled=3D0, enabled=3D0, disabled=3D0 rx_framing_err=3D0, rx_overflow_err=3D0, rx_buffer_err=3D0 rx_bpe_err=3D0, rx_soft_overflow_err=3D0, rx_no_enp=3D0, rx_discard=3D=

0

CISCO2#sho controllers S0/0 Interface Serial0/0 Hardware is PowerQUICC MPC860 with Integrated FT1 CSU/DSU module TX and RX clocks detected. idb at 0x82C01F10, driver data structure at 0x82C09CA4 SCC Registers: General [GSMR]=3D0x2:0x00000030, Protocol-specific [PSMR]=3D0x8 Events [SCCE]=3D0x0000, Mask [SCCM]=3D0x001F, Status [SCCS]=3D0x06 Transmit on Demand [TODR]=3D0x0, Data Sync [DSR]=3D0x7E7E Interrupt Registers: Config [CICR]=3D0x00367F80, Pending [CIPR]=3D0x00008000 Mask [CIMR]=3D0x40204000, In-srv [CISR]=3D0x00000000 Command register [CR]=3D0x600 Port A [PADIR]=3D0x0000, [PAPAR]=3D0xFFFF [PAODR]=3D0x0000, [PADAT]=3D0xEEFF Port B [PBDIR]=3D0x0180F, [PBPAR]=3D0x0000E [PBODR]=3D0x00000, [PBDAT]=3D0x3E77D Port C [PCDIR]=3D0x00C, [PCPAR]=3D0x000 [PCSO]=3D0x020, [PCDAT]=3D0xFC0, [PCINT]=3D0x00F Receive Ring rmd(680126B0): status 9000 length 2E address 3DB7044 rmd(680126B8): status 9000 length 86 address 3DB76C4 rmd(680126C0): status 9000 length 2E address 3DBAAC4 rmd(680126C8): status 9000 length 86 address 3DB9744

CISCO2#sho controllers T1

CISCO2#

Reply to
Tom Linden

"Tom Linden" ha scritto nel messaggio news: snipped-for-privacy@murphus.linden...

Hi,

You don't have to worry about that value (unless you want to tune this for QoS implmenetation). A 25% of "bandwidth" is reserved in such a way that you can't allocate it to RSVP, other QoS features (i.e. Class bandwidth/priority). This is a safeguard for traffic overhead and routing protocol traffic not to be starved if you "reserved" the 100% bandwidth to user traffic. Note that now you can already use your whole "pipe", you are not limited to

1158Kbps

You can tune the value using "max-reserved-bandwidth" interface command

Probably I haven't expressed myself well, so you should see some real documentation about this.

Regards, Gabriele

Reply to
Gabriele Beltrame

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